From 21ef9a711146a3a0737cc3a0b30a4148d7287e18 Mon Sep 17 00:00:00 2001
From: Paolo Tranquilli <redsun82@github.com>
Date: Tue, 26 May 2026 17:51:54 +0200
Subject: [PATCH 1/6] Rust: Add manual regression test for dbscheme upgrade

Adds a test directory with queries that verify properties are preserved
when upgrading databases from rust-analyzer 0.0.301 to 0.0.328.

This is a one-off manual test (not yet in CI), but could serve as the
foundation for a general upgrade testing strategy.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 .../test/.gitignore                           |  3 +
 .../test/README.md                            | 35 +++++++++
 .../test/new/UpgradeShapes.expected           | 20 +++++
 .../test/new/UpgradeShapes.ql                 | 73 +++++++++++++++++++
 .../test/new/qlpack.yml                       |  6 ++
 .../test/new/upgrade_shapes.rs                | 23 ++++++
 .../test/old/OldShapes.expected               | 22 ++++++
 .../test/old/OldShapes.ql                     | 56 ++++++++++++++
 .../test/run-test.sh                          | 62 ++++++++++++++++
 9 files changed, 300 insertions(+)
 create mode 100644 rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/.gitignore
 create mode 100644 rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/README.md
 create mode 100644 rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.expected
 create mode 100644 rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.ql
 create mode 100644 rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/qlpack.yml
 create mode 100644 rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/upgrade_shapes.rs
 create mode 100644 rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.expected
 create mode 100644 rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.ql
 create mode 100755 rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh

diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/.gitignore b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/.gitignore
new file mode 100644
index 000000000000..3b4d77eb40d2
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/.gitignore
@@ -0,0 +1,3 @@
+*.testproj/
+*.actual
+*.log
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/README.md b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/README.md
new file mode 100644
index 000000000000..0acd82f4b421
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/README.md
@@ -0,0 +1,35 @@
+# Rust upgrade preservation test
+
+This directory contains a manual regression test for the Rust dbscheme upgrade from rust-analyzer 0.0.301 to 0.0.328.
+
+It is **not yet checked by CI**. The test has to be run manually because it requires building an old extractor to create an old-schema database first.
+
+## Directory structure
+
+- `old/`: Test query for the **old** schema, showing fields that will be upgraded
+- `new/`: Test query and sources for the **new** schema after upgrade
+
+## Running the test
+
+From anywhere in the repository:
+
+```bash
+rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh
+```
+
+Or override the old commit if needed:
+
+```bash
+OLD_COMMIT=<commit> rust/ql/lib/upgrades/.../test/run-test.sh
+```
+
+The script will:
+1. Copy test files to a temp directory
+2. Stash uncommitted changes and checkout the old commit
+3. Build the old extractor with `bazel run //rust:install`
+4. Create an old-schema database with `codeql test run`
+5. Restore your branch and pop the stash
+6. Upgrade the database to the new schema
+7. Run the preservation test on the upgraded database
+
+If the expected output needs to be refreshed after an intentional query change, manually run the final `codeql test run` with `--learn`.
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.expected b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.expected
new file mode 100644
index 000000000000..6adf4a878beb
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.expected
@@ -0,0 +1,20 @@
+formatArgNamePreserved
+| upgrade_shapes.rs:22:37:22:41 | FormatArgsArg | upgrade_shapes.rs:22:37:22:37 | FormatArgsArgName | upgrade_shapes.rs:22:41:22:41 | 1 | 37 | 1 |
+| upgrade_shapes.rs:22:44:22:48 | FormatArgsArg | upgrade_shapes.rs:22:44:22:44 | FormatArgsArgName | upgrade_shapes.rs:22:48:22:48 | 2 | 44 | 2 |
+tryBlockModifierPreserved
+| upgrade_shapes.rs:21:13:21:21 | { ... } | upgrade_shapes.rs:21:13:21:21 | TryBlockModifier |
+structFieldDefaultPreserved
+| upgrade_shapes.rs:9:5:9:17 | field: u8 | upgrade_shapes.rs:9:17:9:17 | ConstArg | upgrade_shapes.rs:9:17:9:17 | 1 |
+variantDiscriminantPreserved
+| upgrade_shapes.rs:13:5:13:9 | V | upgrade_shapes.rs:13:9:13:9 | ConstArg | upgrade_shapes.rs:13:9:13:9 | 2 |
+pathMetaPreserved
+| upgrade_shapes.rs:4:3:4:11 | PathMeta | path_meta |
+| upgrade_shapes.rs:7:3:7:19 | PathMeta | path_meta |
+keyValueMetaPreserved
+| upgrade_shapes.rs:5:3:5:15 | KeyValueMeta | key_value | upgrade_shapes.rs:5:15:5:15 | 1 |
+tokenTreeMetaPreserved
+| upgrade_shapes.rs:6:3:6:18 | TokenTreeMeta | token_tree | upgrade_shapes.rs:6:13:6:18 | TokenTree |
+unsafeMetaPreserved
+| upgrade_shapes.rs:7:3:7:19 | UnsafeMeta | upgrade_shapes.rs:7:3:7:19 | PathMeta | path_meta |
+traitAliasPreserved
+| upgrade_shapes.rs:16:1:18:12 | trait Alias | upgrade_shapes.rs:16:7:16:11 | Alias | upgrade_shapes.rs:16:18:16:22 | ... | upgrade_shapes.rs:17:1:18:11 | WhereClause |
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.ql b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.ql
new file mode 100644
index 000000000000..bd983a8290c4
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.ql
@@ -0,0 +1,73 @@
+import codeql.rust.elements
+
+private predicate inUpgradeShapesFile(Locatable loc) {
+  loc.getFile().getBaseName() = "upgrade_shapes.rs"
+}
+
+query predicate formatArgNamePreserved(
+  FormatArgsArg arg, FormatArgsArgName argName, Expr expr, int argNameColumn, string exprText
+) {
+  inUpgradeShapesFile(arg) and
+  argName = arg.getArgName() and
+  expr = arg.getExpr() and
+  argNameColumn = argName.getLocation().getStartColumn() and
+  exprText = expr.toString()
+}
+
+query predicate tryBlockModifierPreserved(BlockExpr block, TryBlockModifier modifier) {
+  inUpgradeShapesFile(block) and
+  modifier = block.getTryBlockModifier() and
+  modifier.isTry() and
+  not modifier.hasTypeRepr()
+}
+
+query predicate structFieldDefaultPreserved(StructField field, ConstArg defaultVal, Expr expr) {
+  inUpgradeShapesFile(field) and
+  defaultVal = field.getDefaultVal() and
+  expr = defaultVal.getExpr()
+}
+
+query predicate variantDiscriminantPreserved(Variant variant, ConstArg constArg, Expr expr) {
+  inUpgradeShapesFile(variant) and
+  constArg = variant.getConstArg() and
+  expr = constArg.getExpr()
+}
+
+query predicate pathMetaPreserved(PathMeta meta, string pathText) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "path_meta"
+}
+
+query predicate keyValueMetaPreserved(KeyValueMeta meta, string pathText, Expr expr) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "key_value" and
+  expr = meta.getExpr()
+}
+
+query predicate tokenTreeMetaPreserved(TokenTreeMeta meta, string pathText, TokenTree tokenTree) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "token_tree" and
+  tokenTree = meta.getTokenTree()
+}
+
+query predicate unsafeMetaPreserved(UnsafeMeta meta, PathMeta inner, string pathText) {
+  inUpgradeShapesFile(meta) and
+  meta.isUnsafe() and
+  inner = meta.getMeta() and
+  pathText = inner.getPath().getText() and
+  pathText = "path_meta"
+}
+
+query predicate traitAliasPreserved(
+  Trait trait, Name name, TypeBoundList bounds, WhereClause whereClause
+) {
+  inUpgradeShapesFile(trait) and
+  name = trait.getName() and
+  name.getText() = "Alias" and
+  bounds = trait.getTypeBoundList() and
+  whereClause = trait.getWhereClause() and
+  not trait.hasAssocItemList()
+}
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/qlpack.yml b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/qlpack.yml
new file mode 100644
index 000000000000..81a7b0a25031
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/qlpack.yml
@@ -0,0 +1,6 @@
+name: codeql/rust-upgrade-66a489863649185f4a9770f894505803059a1312-test-new
+version: 0.0.0
+dependencies:
+  codeql/rust-all: ${workspace}
+extractor: rust
+tests: .
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/upgrade_shapes.rs b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/upgrade_shapes.rs
new file mode 100644
index 000000000000..e64d8f6582c6
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/upgrade_shapes.rs
@@ -0,0 +1,23 @@
+#![allow(dead_code)]
+#![feature(more_qualified_paths)]
+
+#[path_meta]
+#[key_value = 1]
+#[token_tree(list)]
+#[unsafe(path_meta)]
+struct S {
+    field: u8 = 1,
+}
+
+enum E {
+    V = 2,
+}
+
+trait Alias<T> = Clone
+where
+    T: Copy;
+
+fn f() {
+    let _ = try { 1 };
+    let _ = format_args!("{b} {a}", a = 1, b = 2);
+}
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.expected b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.expected
new file mode 100644
index 000000000000..8cb5c2511a44
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.expected
@@ -0,0 +1,22 @@
+formatArgsArgName
+| upgrade_shapes.rs:22:31:22:31 | a | upgrade_shapes.rs:22:35:22:35 | 1 | a |
+| upgrade_shapes.rs:22:38:22:38 | b | upgrade_shapes.rs:22:42:22:42 | 2 | b |
+metaExpr
+| upgrade_shapes.rs:5:1:5:15 | #[key_value = 1] | upgrade_shapes.rs:5:15:5:15 | 1 |
+metaIsUnsafe
+| upgrade_shapes.rs:7:1:7:21 | #[unsafe(path_meta)] | 
+metaPath
+| upgrade_shapes.rs:4:1:4:12 | #[path_meta] | path_meta |
+| upgrade_shapes.rs:5:1:5:15 | #[key_value = 1] | key_value |
+| upgrade_shapes.rs:6:1:6:19 | #[token_tree(list)] | token_tree |
+| upgrade_shapes.rs:7:1:7:21 | #[unsafe(path_meta)] | path_meta |
+metaTokenTree
+| upgrade_shapes.rs:6:1:6:19 | #[token_tree(list)] | upgrade_shapes.rs:6:13:6:18 | (list) |
+structFieldDefault
+| upgrade_shapes.rs:9:5:9:17 | field: u8 = 1 | upgrade_shapes.rs:9:17:9:17 | 1 |
+traitAlias
+| upgrade_shapes.rs:16:1:18:12 | TraitAlias | Alias | upgrade_shapes.rs:16:18:16:23 | = Clone | upgrade_shapes.rs:17:1:18:12 | where... |
+tryBlock
+| upgrade_shapes.rs:21:13:21:23 | try { 1 } |
+variantDiscriminant
+| upgrade_shapes.rs:13:5:13:9 | V = 2 | upgrade_shapes.rs:13:9:13:9 | 2 |
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.ql b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.ql
new file mode 100644
index 000000000000..ced2690b7dbb
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.ql
@@ -0,0 +1,56 @@
+import codeql.rust.elements
+
+private predicate inUpgradeShapesFile(Locatable loc) {
+  loc.getFile().getBaseName() = "upgrade_shapes.rs"
+}
+
+query predicate formatArgsArgName(FormatArgsArg arg, Name argName, Expr expr, string nameText) {
+  inUpgradeShapesFile(arg) and
+  argName = arg.getName() and
+  expr = arg.getExpr() and
+  nameText = argName.getText()
+}
+
+query predicate tryBlock(BlockExpr block) {
+  inUpgradeShapesFile(block) and
+  block.isTry()
+}
+
+query predicate structFieldDefault(StructField field, Expr defaultVal) {
+  inUpgradeShapesFile(field) and
+  defaultVal = field.getDefault()
+}
+
+query predicate variantDiscriminant(Variant variant, Expr discriminant) {
+  inUpgradeShapesFile(variant) and
+  discriminant = variant.getDiscriminant()
+}
+
+query predicate metaPath(Meta meta, string pathText) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText()
+}
+
+query predicate metaExpr(Meta meta, Expr expr) {
+  inUpgradeShapesFile(meta) and
+  expr = meta.getExpr()
+}
+
+query predicate metaTokenTree(Meta meta, TokenTree tokenTree) {
+  inUpgradeShapesFile(meta) and
+  tokenTree = meta.getTokenTree()
+}
+
+query predicate metaIsUnsafe(Meta meta) {
+  inUpgradeShapesFile(meta) and
+  meta.isUnsafe()
+}
+
+query predicate traitAlias(
+  TraitAlias alias, Name name, TypeBoundList bounds, WhereClause whereClause
+) {
+  inUpgradeShapesFile(alias) and
+  name = alias.getName() and
+  bounds = alias.getTypeBoundList() and
+  whereClause = alias.getWhereClause()
+}
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh
new file mode 100755
index 000000000000..93e79ff4daae
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh
@@ -0,0 +1,62 @@
+#!/usr/bin/env bash
+# Manual regression test for the Rust dbscheme upgrade from rust-analyzer 0.0.301 to 0.0.328.
+# See README.md for details.
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_ROOT="$(cd "$SCRIPT_DIR/../../../../.." && pwd)"
+OLD_COMMIT="${OLD_COMMIT:-491c373e076}"  # origin/main at time of this upgrade
+
+cd "$REPO_ROOT"
+
+echo "==> Setting up temp directory for old test..."
+OLD_TEST_TMP=$(mktemp -d)
+trap 'rm -rf "$OLD_TEST_TMP"' EXIT
+
+# Copy old test query and new test sources (qlpack, upgrade_shapes.rs) to temp
+cp "$SCRIPT_DIR/old/OldShapes.ql" "$SCRIPT_DIR/old/OldShapes.expected" "$OLD_TEST_TMP/"
+cp "$SCRIPT_DIR/new/qlpack.yml" "$SCRIPT_DIR/new/upgrade_shapes.rs" "$OLD_TEST_TMP/"
+
+echo "==> Stashing any uncommitted changes..."
+git stash --quiet || true
+
+restore_branch() {
+    echo "==> Restoring original branch..."
+    git checkout --quiet -
+    git stash pop --quiet 2>/dev/null || true
+}
+trap 'restore_branch; rm -rf "$OLD_TEST_TMP"' EXIT
+
+echo "==> Checking out old commit ($OLD_COMMIT)..."
+git checkout --quiet "$OLD_COMMIT"
+
+echo "==> Building old extractor (this may take a while)..."
+bazel run //rust:install
+
+echo "==> Creating old-schema test database..."
+rm -rf "$OLD_TEST_TMP"/*.testproj
+codeql test run \
+    --search-path . \
+    --keep-databases \
+    "$OLD_TEST_TMP/OldShapes.ql"
+
+echo "==> Copying dataset for upgrade..."
+cp -a "$OLD_TEST_TMP/test.testproj/db-rust" "$OLD_TEST_TMP/upgraded-dataset"
+
+restore_branch
+trap 'rm -rf "$OLD_TEST_TMP"' EXIT
+
+echo "==> Upgrading dataset to new schema..."
+codeql dataset upgrade "$OLD_TEST_TMP/upgraded-dataset" \
+    --search-path . \
+    --target-dbscheme rust/ql/lib/rust.dbscheme
+
+echo "==> Running preservation test on upgraded dataset..."
+codeql test run \
+    --search-path . \
+    --dataset="$OLD_TEST_TMP/upgraded-dataset" \
+    --check-databases \
+    "$SCRIPT_DIR/new/UpgradeShapes.ql"
+
+echo "==> All tests passed!"

From 27f8d9573d3b460608550cf295e5736e0b6a9390 Mon Sep 17 00:00:00 2001
From: Paolo Tranquilli <redsun82@github.com>
Date: Tue, 26 May 2026 18:17:03 +0200
Subject: [PATCH 2/6] Fix REPO_ROOT computation in run-test.sh

Use `git rev-parse --show-toplevel` instead of fragile relative path.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 .../66a489863649185f4a9770f894505803059a1312/test/run-test.sh   | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh
index 93e79ff4daae..a4e8e9f53a87 100755
--- a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh
@@ -5,7 +5,7 @@
 set -euo pipefail
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
-REPO_ROOT="$(cd "$SCRIPT_DIR/../../../../.." && pwd)"
+REPO_ROOT="$(git rev-parse --show-toplevel)"
 OLD_COMMIT="${OLD_COMMIT:-491c373e076}"  # origin/main at time of this upgrade
 
 cd "$REPO_ROOT"

From b293a4dd8c86263f97ad137706e3a153d6456eb7 Mon Sep 17 00:00:00 2001
From: Paolo Tranquilli <redsun82@github.com>
Date: Wed, 27 May 2026 08:13:04 +0200
Subject: [PATCH 3/6] Fix unsafe stash handling in run-test.sh

Only stash when there are actual changes (including untracked files),
and only pop the specific stash entry we created.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 .../test/run-test.sh                              | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh
index a4e8e9f53a87..a3f65d9897c4 100755
--- a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh
@@ -18,13 +18,22 @@ trap 'rm -rf "$OLD_TEST_TMP"' EXIT
 cp "$SCRIPT_DIR/old/OldShapes.ql" "$SCRIPT_DIR/old/OldShapes.expected" "$OLD_TEST_TMP/"
 cp "$SCRIPT_DIR/new/qlpack.yml" "$SCRIPT_DIR/new/upgrade_shapes.rs" "$OLD_TEST_TMP/"
 
-echo "==> Stashing any uncommitted changes..."
-git stash --quiet || true
+# Stash changes only if there are any (including untracked files)
+STASH_REF=""
+if ! git diff --quiet HEAD || [ -n "$(git ls-files --others --exclude-standard)" ]; then
+    echo "==> Stashing uncommitted changes..."
+    STASH_REF=$(git stash create --include-untracked)
+    if [ -n "$STASH_REF" ]; then
+        git stash store -m "run-test.sh auto-stash" "$STASH_REF"
+    fi
+fi
 
 restore_branch() {
     echo "==> Restoring original branch..."
     git checkout --quiet -
-    git stash pop --quiet 2>/dev/null || true
+    if [ -n "$STASH_REF" ]; then
+        git stash pop --quiet
+    fi
 }
 trap 'restore_branch; rm -rf "$OLD_TEST_TMP"' EXIT
 

From 9abd08ceaea0853526d7d3cb91de8a851345f70a Mon Sep 17 00:00:00 2001
From: Paolo Tranquilli <redsun82@github.com>
Date: Wed, 27 May 2026 08:54:17 +0200
Subject: [PATCH 4/6] Rust: Move upgrade test to separate `upgrade-tests`
 directory

Avoids issues with nested qlpack.yml breaking `codeql pack create` for the lib pack.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 codeql-workspace.yml                          |  1 +
 rust/ql/upgrade-tests/.gitignore              |  9 +++
 .../.gitignore                                |  3 +
 .../README.md                                 | 25 +++++++
 .../new.expected                              | 20 +++++
 .../new.ql                                    | 73 +++++++++++++++++++
 .../old.expected                              | 26 +++++++
 .../old.ql                                    | 56 ++++++++++++++
 .../run-test.sh                               | 67 +++++++++++++++++
 .../upgrade_shapes.rs                         | 23 ++++++
 rust/ql/upgrade-tests/qlpack.yml              |  5 ++
 11 files changed, 308 insertions(+)
 create mode 100644 rust/ql/upgrade-tests/.gitignore
 create mode 100644 rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
 create mode 100644 rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
 create mode 100644 rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/new.expected
 create mode 100644 rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/new.ql
 create mode 100644 rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/old.expected
 create mode 100644 rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/old.ql
 create mode 100755 rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
 create mode 100644 rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/upgrade_shapes.rs
 create mode 100644 rust/ql/upgrade-tests/qlpack.yml

diff --git a/codeql-workspace.yml b/codeql-workspace.yml
index 32cad09e20c7..a6408dc26ecf 100644
--- a/codeql-workspace.yml
+++ b/codeql-workspace.yml
@@ -2,6 +2,7 @@ provide:
   - "*/ql/src/qlpack.yml"
   - "*/ql/lib/qlpack.yml"
   - "*/ql/test*/qlpack.yml"
+  - "*/ql/upgrade-tests/qlpack.yml"
   - "*/ql/examples/qlpack.yml"
   - "*/ql/consistency-queries/qlpack.yml"
   - "*/ql/automodel/src/qlpack.yml"
diff --git a/rust/ql/upgrade-tests/.gitignore b/rust/ql/upgrade-tests/.gitignore
new file mode 100644
index 000000000000..29291fe2d12c
--- /dev/null
+++ b/rust/ql/upgrade-tests/.gitignore
@@ -0,0 +1,9 @@
+target/
+
+# these are all generated, see `rust/extractor/src/qltest.rs` for details
+Cargo.toml
+/*/**/rust-toolchain.toml
+lib.rs
+.proc_macro/
+.lib/
+
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
new file mode 100644
index 000000000000..3b4d77eb40d2
--- /dev/null
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
@@ -0,0 +1,3 @@
+*.testproj/
+*.actual
+*.log
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
new file mode 100644
index 000000000000..ecc94261ee51
--- /dev/null
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
@@ -0,0 +1,25 @@
+# Upgrade Regression Test for rust-analyzer 0.0.301 → 0.0.328
+
+This test verifies that the dbscheme upgrade script correctly preserves data when migrating databases from the old schema to the new schema.
+
+## Running the test
+
+```bash
+./run-test.sh
+```
+
+This will:
+1. Stash any uncommitted changes
+2. Check out the old commit (491c373e076)
+3. Build the old extractor
+4. Create a database with the old schema from `upgrade_shapes.rs`
+5. Restore your branch
+6. Upgrade the database to the new schema
+7. Verify that the old properties are still accessible via the new schema
+
+## Files
+
+- `old.ql` / `old.expected`: Query for the old schema (validates extraction)
+- `new.ql` / `new.expected`: Query for the new schema (validates upgrade preserved data)
+- `upgrade_shapes.rs`: Rust source containing test shapes for all affected schema elements
+- `run-test.sh`: Test runner script
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/new.expected b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/new.expected
new file mode 100644
index 000000000000..6adf4a878beb
--- /dev/null
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/new.expected
@@ -0,0 +1,20 @@
+formatArgNamePreserved
+| upgrade_shapes.rs:22:37:22:41 | FormatArgsArg | upgrade_shapes.rs:22:37:22:37 | FormatArgsArgName | upgrade_shapes.rs:22:41:22:41 | 1 | 37 | 1 |
+| upgrade_shapes.rs:22:44:22:48 | FormatArgsArg | upgrade_shapes.rs:22:44:22:44 | FormatArgsArgName | upgrade_shapes.rs:22:48:22:48 | 2 | 44 | 2 |
+tryBlockModifierPreserved
+| upgrade_shapes.rs:21:13:21:21 | { ... } | upgrade_shapes.rs:21:13:21:21 | TryBlockModifier |
+structFieldDefaultPreserved
+| upgrade_shapes.rs:9:5:9:17 | field: u8 | upgrade_shapes.rs:9:17:9:17 | ConstArg | upgrade_shapes.rs:9:17:9:17 | 1 |
+variantDiscriminantPreserved
+| upgrade_shapes.rs:13:5:13:9 | V | upgrade_shapes.rs:13:9:13:9 | ConstArg | upgrade_shapes.rs:13:9:13:9 | 2 |
+pathMetaPreserved
+| upgrade_shapes.rs:4:3:4:11 | PathMeta | path_meta |
+| upgrade_shapes.rs:7:3:7:19 | PathMeta | path_meta |
+keyValueMetaPreserved
+| upgrade_shapes.rs:5:3:5:15 | KeyValueMeta | key_value | upgrade_shapes.rs:5:15:5:15 | 1 |
+tokenTreeMetaPreserved
+| upgrade_shapes.rs:6:3:6:18 | TokenTreeMeta | token_tree | upgrade_shapes.rs:6:13:6:18 | TokenTree |
+unsafeMetaPreserved
+| upgrade_shapes.rs:7:3:7:19 | UnsafeMeta | upgrade_shapes.rs:7:3:7:19 | PathMeta | path_meta |
+traitAliasPreserved
+| upgrade_shapes.rs:16:1:18:12 | trait Alias | upgrade_shapes.rs:16:7:16:11 | Alias | upgrade_shapes.rs:16:18:16:22 | ... | upgrade_shapes.rs:17:1:18:11 | WhereClause |
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/new.ql b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/new.ql
new file mode 100644
index 000000000000..bd983a8290c4
--- /dev/null
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/new.ql
@@ -0,0 +1,73 @@
+import codeql.rust.elements
+
+private predicate inUpgradeShapesFile(Locatable loc) {
+  loc.getFile().getBaseName() = "upgrade_shapes.rs"
+}
+
+query predicate formatArgNamePreserved(
+  FormatArgsArg arg, FormatArgsArgName argName, Expr expr, int argNameColumn, string exprText
+) {
+  inUpgradeShapesFile(arg) and
+  argName = arg.getArgName() and
+  expr = arg.getExpr() and
+  argNameColumn = argName.getLocation().getStartColumn() and
+  exprText = expr.toString()
+}
+
+query predicate tryBlockModifierPreserved(BlockExpr block, TryBlockModifier modifier) {
+  inUpgradeShapesFile(block) and
+  modifier = block.getTryBlockModifier() and
+  modifier.isTry() and
+  not modifier.hasTypeRepr()
+}
+
+query predicate structFieldDefaultPreserved(StructField field, ConstArg defaultVal, Expr expr) {
+  inUpgradeShapesFile(field) and
+  defaultVal = field.getDefaultVal() and
+  expr = defaultVal.getExpr()
+}
+
+query predicate variantDiscriminantPreserved(Variant variant, ConstArg constArg, Expr expr) {
+  inUpgradeShapesFile(variant) and
+  constArg = variant.getConstArg() and
+  expr = constArg.getExpr()
+}
+
+query predicate pathMetaPreserved(PathMeta meta, string pathText) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "path_meta"
+}
+
+query predicate keyValueMetaPreserved(KeyValueMeta meta, string pathText, Expr expr) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "key_value" and
+  expr = meta.getExpr()
+}
+
+query predicate tokenTreeMetaPreserved(TokenTreeMeta meta, string pathText, TokenTree tokenTree) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "token_tree" and
+  tokenTree = meta.getTokenTree()
+}
+
+query predicate unsafeMetaPreserved(UnsafeMeta meta, PathMeta inner, string pathText) {
+  inUpgradeShapesFile(meta) and
+  meta.isUnsafe() and
+  inner = meta.getMeta() and
+  pathText = inner.getPath().getText() and
+  pathText = "path_meta"
+}
+
+query predicate traitAliasPreserved(
+  Trait trait, Name name, TypeBoundList bounds, WhereClause whereClause
+) {
+  inUpgradeShapesFile(trait) and
+  name = trait.getName() and
+  name.getText() = "Alias" and
+  bounds = trait.getTypeBoundList() and
+  whereClause = trait.getWhereClause() and
+  not trait.hasAssocItemList()
+}
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/old.expected b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/old.expected
new file mode 100644
index 000000000000..4fb40adf86f1
--- /dev/null
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/old.expected
@@ -0,0 +1,26 @@
+formatArgsArgName
+| upgrade_shapes.rs:22:37:22:41 | FormatArgsArg | upgrade_shapes.rs:22:37:22:37 | a | upgrade_shapes.rs:22:41:22:41 | 1 | a |
+| upgrade_shapes.rs:22:44:22:48 | FormatArgsArg | upgrade_shapes.rs:22:44:22:44 | b | upgrade_shapes.rs:22:48:22:48 | 2 | b |
+tryBlock
+| upgrade_shapes.rs:21:13:21:21 | { ... } |
+structFieldDefault
+| upgrade_shapes.rs:9:5:9:17 | field: u8 | upgrade_shapes.rs:9:17:9:17 | 1 |
+variantDiscriminant
+| upgrade_shapes.rs:13:5:13:9 | V | upgrade_shapes.rs:13:9:13:9 | 2 |
+metaPath
+| upgrade_shapes.rs:1:4:1:19 | Meta | allow |
+| upgrade_shapes.rs:2:4:2:32 | Meta | feature |
+| upgrade_shapes.rs:4:3:4:11 | Meta | path_meta |
+| upgrade_shapes.rs:5:3:5:15 | Meta | key_value |
+| upgrade_shapes.rs:6:3:6:18 | Meta | token_tree |
+| upgrade_shapes.rs:7:3:7:19 | Meta | path_meta |
+metaExpr
+| upgrade_shapes.rs:5:3:5:15 | Meta | upgrade_shapes.rs:5:15:5:15 | 1 |
+metaTokenTree
+| upgrade_shapes.rs:1:4:1:19 | Meta | upgrade_shapes.rs:1:9:1:19 | TokenTree |
+| upgrade_shapes.rs:2:4:2:32 | Meta | upgrade_shapes.rs:2:11:2:32 | TokenTree |
+| upgrade_shapes.rs:6:3:6:18 | Meta | upgrade_shapes.rs:6:13:6:18 | TokenTree |
+metaIsUnsafe
+| upgrade_shapes.rs:7:3:7:19 | Meta |
+traitAlias
+| upgrade_shapes.rs:16:1:18:12 | TraitAlias | upgrade_shapes.rs:16:7:16:11 | Alias | upgrade_shapes.rs:16:18:16:22 | ... | upgrade_shapes.rs:17:1:18:11 | WhereClause |
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/old.ql b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/old.ql
new file mode 100644
index 000000000000..ced2690b7dbb
--- /dev/null
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/old.ql
@@ -0,0 +1,56 @@
+import codeql.rust.elements
+
+private predicate inUpgradeShapesFile(Locatable loc) {
+  loc.getFile().getBaseName() = "upgrade_shapes.rs"
+}
+
+query predicate formatArgsArgName(FormatArgsArg arg, Name argName, Expr expr, string nameText) {
+  inUpgradeShapesFile(arg) and
+  argName = arg.getName() and
+  expr = arg.getExpr() and
+  nameText = argName.getText()
+}
+
+query predicate tryBlock(BlockExpr block) {
+  inUpgradeShapesFile(block) and
+  block.isTry()
+}
+
+query predicate structFieldDefault(StructField field, Expr defaultVal) {
+  inUpgradeShapesFile(field) and
+  defaultVal = field.getDefault()
+}
+
+query predicate variantDiscriminant(Variant variant, Expr discriminant) {
+  inUpgradeShapesFile(variant) and
+  discriminant = variant.getDiscriminant()
+}
+
+query predicate metaPath(Meta meta, string pathText) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText()
+}
+
+query predicate metaExpr(Meta meta, Expr expr) {
+  inUpgradeShapesFile(meta) and
+  expr = meta.getExpr()
+}
+
+query predicate metaTokenTree(Meta meta, TokenTree tokenTree) {
+  inUpgradeShapesFile(meta) and
+  tokenTree = meta.getTokenTree()
+}
+
+query predicate metaIsUnsafe(Meta meta) {
+  inUpgradeShapesFile(meta) and
+  meta.isUnsafe()
+}
+
+query predicate traitAlias(
+  TraitAlias alias, Name name, TypeBoundList bounds, WhereClause whereClause
+) {
+  inUpgradeShapesFile(alias) and
+  name = alias.getName() and
+  bounds = alias.getTypeBoundList() and
+  whereClause = alias.getWhereClause()
+}
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
new file mode 100755
index 000000000000..b5ae0d8a42f7
--- /dev/null
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+# Manual regression test for the Rust dbscheme upgrade from rust-analyzer 0.0.301 to 0.0.328.
+# See README.md for details.
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_ROOT="$(git rev-parse --show-toplevel)"
+OLD_COMMIT="${OLD_COMMIT:-491c373e076}"  # origin/main at time of this upgrade
+
+cd "$REPO_ROOT"
+
+# Require clean working directory - stash handling is too fragile
+if ! git diff --quiet HEAD || [ -n "$(git ls-files --others --exclude-standard)" ]; then
+    echo "ERROR: Working directory has uncommitted changes." >&2
+    echo "Please commit or stash your changes before running this test." >&2
+    exit 1
+fi
+
+ORIGINAL_REF="$(git rev-parse --abbrev-ref HEAD)"
+if [ "$ORIGINAL_REF" = "HEAD" ]; then
+    # Detached HEAD - save the commit instead
+    ORIGINAL_REF="$(git rev-parse HEAD)"
+fi
+
+restore_ref() {
+    echo "==> Restoring original ref ($ORIGINAL_REF)..."
+    git checkout --quiet "$ORIGINAL_REF"
+}
+trap 'restore_ref' EXIT
+
+echo "==> Checking out old commit ($OLD_COMMIT)..."
+git checkout --quiet "$OLD_COMMIT"
+
+# Restore the upgrade-tests directory from the original ref (it doesn't exist in old commit)
+git checkout --quiet "$ORIGINAL_REF" -- rust/ql/upgrade-tests codeql-workspace.yml
+
+echo "==> Building old extractor (this may take a while)..."
+bazel run //rust:install
+
+echo "==> Creating old-schema test database..."
+codeql test run \
+    --search-path . \
+    --keep-databases \
+    "$SCRIPT_DIR/old.ql" "$@"
+
+restore_ref
+trap '' EXIT
+
+echo "==> Upgrading dataset to new schema..."
+DATASET_DIR=("$SCRIPT_DIR"/*.testproj/db-rust)
+if [[ ! -d "${DATASET_DIR[0]}" ]]; then
+    echo "ERROR: No testproj found at $SCRIPT_DIR/*.testproj" >&2
+    exit 1
+fi
+codeql dataset upgrade "${DATASET_DIR[0]}" \
+    --search-path . \
+    --target-dbscheme rust/ql/lib/rust.dbscheme
+
+echo "==> Running preservation test on upgraded dataset..."
+codeql test run \
+    --search-path . \
+    --dataset "${DATASET_DIR[0]}" \
+    --check-databases \
+    "$SCRIPT_DIR/new.ql" "$@"
+
+echo "==> All tests passed!"
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/upgrade_shapes.rs b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/upgrade_shapes.rs
new file mode 100644
index 000000000000..e64d8f6582c6
--- /dev/null
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/upgrade_shapes.rs
@@ -0,0 +1,23 @@
+#![allow(dead_code)]
+#![feature(more_qualified_paths)]
+
+#[path_meta]
+#[key_value = 1]
+#[token_tree(list)]
+#[unsafe(path_meta)]
+struct S {
+    field: u8 = 1,
+}
+
+enum E {
+    V = 2,
+}
+
+trait Alias<T> = Clone
+where
+    T: Copy;
+
+fn f() {
+    let _ = try { 1 };
+    let _ = format_args!("{b} {a}", a = 1, b = 2);
+}
diff --git a/rust/ql/upgrade-tests/qlpack.yml b/rust/ql/upgrade-tests/qlpack.yml
new file mode 100644
index 000000000000..559bca6042af
--- /dev/null
+++ b/rust/ql/upgrade-tests/qlpack.yml
@@ -0,0 +1,5 @@
+name: codeql/rust-upgrade-tests
+version: 0.0.0
+extractor: rust
+dependencies:
+  codeql/rust-all: ${workspace}

From 1a4db88715abebe90627d38fdf4d11c9557d0db3 Mon Sep 17 00:00:00 2001
From: Paolo Tranquilli <redsun82@github.com>
Date: Wed, 27 May 2026 09:35:26 +0200
Subject: [PATCH 5/6] Rust: Test dbscheme downgrade preservation

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 .../README.md                                 |  7 ++-
 .../downgraded.expected                       | 26 +++++++++
 .../downgraded.ql                             | 56 +++++++++++++++++++
 .../run-test.sh                               | 23 ++++++++
 4 files changed, 110 insertions(+), 2 deletions(-)
 create mode 100644 rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
 create mode 100644 rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.ql

diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
index ecc94261ee51..a728458bef42 100644
--- a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
@@ -1,6 +1,6 @@
 # Upgrade Regression Test for rust-analyzer 0.0.301 → 0.0.328
 
-This test verifies that the dbscheme upgrade script correctly preserves data when migrating databases from the old schema to the new schema.
+This test verifies that the dbscheme upgrade and downgrade scripts correctly preserve data when migrating databases between the old and new schemas.
 
 ## Running the test
 
@@ -16,10 +16,13 @@ This will:
 5. Restore your branch
 6. Upgrade the database to the new schema
 7. Verify that the old properties are still accessible via the new schema
+8. Downgrade the database back to the old schema
+9. Verify that the recovered old-schema properties still match
 
 ## Files
 
-- `old.ql` / `old.expected`: Query for the old schema (validates extraction)
+- `old.ql` / `old.expected`: Query for the old schema (validates extraction and downgrade)
 - `new.ql` / `new.expected`: Query for the new schema (validates upgrade preserved data)
+- `downgraded.ql` / `downgraded.expected`: Query for the downgraded old schema
 - `upgrade_shapes.rs`: Rust source containing test shapes for all affected schema elements
 - `run-test.sh`: Test runner script
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
new file mode 100644
index 000000000000..1df9e112bbee
--- /dev/null
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
@@ -0,0 +1,26 @@
+formatArgsArgName
+| upgrade_shapes.rs:22:37:22:41 | FormatArgsArg | upgrade_shapes.rs:22:37:22:37 | (no string representation) | upgrade_shapes.rs:22:41:22:41 | 1 | 37 |
+| upgrade_shapes.rs:22:44:22:48 | FormatArgsArg | upgrade_shapes.rs:22:44:22:44 | (no string representation) | upgrade_shapes.rs:22:48:22:48 | 2 | 44 |
+tryBlock
+| upgrade_shapes.rs:21:13:21:21 | { ... } |
+structFieldDefault
+| upgrade_shapes.rs:9:5:9:17 | field: u8 | upgrade_shapes.rs:9:17:9:17 | 1 |
+variantDiscriminant
+| upgrade_shapes.rs:13:5:13:9 | V | upgrade_shapes.rs:13:9:13:9 | 2 |
+metaPath
+| upgrade_shapes.rs:1:4:1:19 | Meta | allow |
+| upgrade_shapes.rs:2:4:2:32 | Meta | feature |
+| upgrade_shapes.rs:4:3:4:11 | Meta | path_meta |
+| upgrade_shapes.rs:5:3:5:15 | Meta | key_value |
+| upgrade_shapes.rs:6:3:6:18 | Meta | token_tree |
+| upgrade_shapes.rs:7:3:7:19 | Meta | path_meta |
+metaExpr
+| upgrade_shapes.rs:5:3:5:15 | Meta | upgrade_shapes.rs:5:15:5:15 | 1 |
+metaTokenTree
+| upgrade_shapes.rs:1:4:1:19 | Meta | upgrade_shapes.rs:1:9:1:19 | TokenTree |
+| upgrade_shapes.rs:2:4:2:32 | Meta | upgrade_shapes.rs:2:11:2:32 | TokenTree |
+| upgrade_shapes.rs:6:3:6:18 | Meta | upgrade_shapes.rs:6:13:6:18 | TokenTree |
+metaIsUnsafe
+| upgrade_shapes.rs:7:3:7:19 | Meta |
+traitAlias
+| upgrade_shapes.rs:16:1:18:12 | TraitAlias | upgrade_shapes.rs:16:7:16:11 | Alias | upgrade_shapes.rs:16:18:16:22 | ... | upgrade_shapes.rs:17:1:18:11 | WhereClause |
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.ql b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.ql
new file mode 100644
index 000000000000..4282fbefa0be
--- /dev/null
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.ql
@@ -0,0 +1,56 @@
+import codeql.rust.elements
+
+private predicate inUpgradeShapesFile(Locatable loc) {
+  loc.getFile().getBaseName() = "upgrade_shapes.rs"
+}
+
+query predicate formatArgsArgName(FormatArgsArg arg, Name argName, Expr expr, int argNameColumn) {
+  inUpgradeShapesFile(arg) and
+  argName = arg.getName() and
+  expr = arg.getExpr() and
+  argNameColumn = argName.getLocation().getStartColumn()
+}
+
+query predicate tryBlock(BlockExpr block) {
+  inUpgradeShapesFile(block) and
+  block.isTry()
+}
+
+query predicate structFieldDefault(StructField field, Expr defaultVal) {
+  inUpgradeShapesFile(field) and
+  defaultVal = field.getDefault()
+}
+
+query predicate variantDiscriminant(Variant variant, Expr discriminant) {
+  inUpgradeShapesFile(variant) and
+  discriminant = variant.getDiscriminant()
+}
+
+query predicate metaPath(Meta meta, string pathText) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText()
+}
+
+query predicate metaExpr(Meta meta, Expr expr) {
+  inUpgradeShapesFile(meta) and
+  expr = meta.getExpr()
+}
+
+query predicate metaTokenTree(Meta meta, TokenTree tokenTree) {
+  inUpgradeShapesFile(meta) and
+  tokenTree = meta.getTokenTree()
+}
+
+query predicate metaIsUnsafe(Meta meta) {
+  inUpgradeShapesFile(meta) and
+  meta.isUnsafe()
+}
+
+query predicate traitAlias(
+  TraitAlias alias, Name name, TypeBoundList bounds, WhereClause whereClause
+) {
+  inUpgradeShapesFile(alias) and
+  name = alias.getName() and
+  bounds = alias.getTypeBoundList() and
+  whereClause = alias.getWhereClause()
+}
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
index b5ae0d8a42f7..1dbbf2783b7a 100755
--- a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
@@ -7,6 +7,7 @@ set -euo pipefail
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 REPO_ROOT="$(git rev-parse --show-toplevel)"
 OLD_COMMIT="${OLD_COMMIT:-491c373e076}"  # origin/main at time of this upgrade
+OLD_DBSCHEME="rust/downgrades/109496fd2f20f28a35e50b110859e74882ee80d6/rust.dbscheme"
 
 cd "$REPO_ROOT"
 
@@ -64,4 +65,26 @@ codeql test run \
     --check-databases \
     "$SCRIPT_DIR/new.ql" "$@"
 
+echo "==> Downgrading dataset back to old schema..."
+codeql dataset upgrade "${DATASET_DIR[0]}" \
+    --allow-downgrades \
+    --search-path rust \
+    --target-dbscheme "$OLD_DBSCHEME"
+
+trap 'restore_ref' EXIT
+
+echo "==> Checking out old commit ($OLD_COMMIT) for downgrade verification..."
+git checkout --quiet "$OLD_COMMIT"
+git checkout --quiet "$ORIGINAL_REF" -- rust/ql/upgrade-tests codeql-workspace.yml
+
+echo "==> Running preservation test on downgraded dataset..."
+codeql test run \
+    --search-path . \
+    --dataset "${DATASET_DIR[0]}" \
+    --check-databases \
+    "$SCRIPT_DIR/downgraded.ql" "$@"
+
+restore_ref
+trap '' EXIT
+
 echo "==> All tests passed!"

From ebf899e89b07e9228a63077bdffaf53f271432be Mon Sep 17 00:00:00 2001
From: Paolo Tranquilli <redsun82@github.com>
Date: Wed, 27 May 2026 10:25:53 +0200
Subject: [PATCH 6/6] Rust: Split downgrade preservation test

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 codeql-workspace.yml                          |  1 +
 rust/ql/downgrade-tests/.gitignore            |  3 +
 .../.gitignore                                |  5 ++
 .../README.md                                 | 24 ++++++
 .../downgraded.expected                       |  4 +-
 .../downgraded.ql                             |  0
 .../new.expected                              | 20 +++++
 .../new.ql                                    | 73 +++++++++++++++++++
 .../run-test.sh                               | 65 +++++++++++++++++
 .../upgrade_shapes.rs                         | 23 ++++++
 rust/ql/downgrade-tests/qlpack.yml            |  5 ++
 .../.gitignore                                |  2 +
 .../README.md                                 |  7 +-
 .../run-test.sh                               | 23 ------
 14 files changed, 225 insertions(+), 30 deletions(-)
 create mode 100644 rust/ql/downgrade-tests/.gitignore
 create mode 100644 rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
 create mode 100644 rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
 rename rust/ql/{upgrade-tests => downgrade-tests}/66a489863649185f4a9770f894505803059a1312/downgraded.expected (87%)
 rename rust/ql/{upgrade-tests => downgrade-tests}/66a489863649185f4a9770f894505803059a1312/downgraded.ql (100%)
 create mode 100644 rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.expected
 create mode 100644 rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.ql
 create mode 100755 rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
 create mode 100644 rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/upgrade_shapes.rs
 create mode 100644 rust/ql/downgrade-tests/qlpack.yml

diff --git a/codeql-workspace.yml b/codeql-workspace.yml
index a6408dc26ecf..c61313163e56 100644
--- a/codeql-workspace.yml
+++ b/codeql-workspace.yml
@@ -3,6 +3,7 @@ provide:
   - "*/ql/lib/qlpack.yml"
   - "*/ql/test*/qlpack.yml"
   - "*/ql/upgrade-tests/qlpack.yml"
+  - "*/ql/downgrade-tests/qlpack.yml"
   - "*/ql/examples/qlpack.yml"
   - "*/ql/consistency-queries/qlpack.yml"
   - "*/ql/automodel/src/qlpack.yml"
diff --git a/rust/ql/downgrade-tests/.gitignore b/rust/ql/downgrade-tests/.gitignore
new file mode 100644
index 000000000000..3b4d77eb40d2
--- /dev/null
+++ b/rust/ql/downgrade-tests/.gitignore
@@ -0,0 +1,3 @@
+*.testproj/
+*.actual
+*.log
diff --git a/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
new file mode 100644
index 000000000000..1abb3d60e268
--- /dev/null
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
@@ -0,0 +1,5 @@
+*.testproj/
+*.actual
+*.log
+Cargo.toml
+lib.rs
diff --git a/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
new file mode 100644
index 000000000000..3cc35fab4774
--- /dev/null
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
@@ -0,0 +1,24 @@
+# Downgrade Regression Test for rust-analyzer 0.0.328 -> 0.0.301
+
+This test verifies that the dbscheme downgrade script correctly preserves recoverable data when migrating databases from the new schema back to the old schema.
+
+## Running the test
+
+```bash
+./run-test.sh
+```
+
+This will:
+1. Build the current extractor
+2. Create a database with the new schema from `upgrade_shapes.rs`
+3. Validate the new-schema extraction
+4. Downgrade the database to the old schema
+5. Check out the old commit (491c373e076)
+6. Verify that the recovered old-schema properties still match
+
+## Files
+
+- `new.ql` / `new.expected`: Query for the new schema (validates extraction)
+- `downgraded.ql` / `downgraded.expected`: Query for the downgraded old schema
+- `upgrade_shapes.rs`: Rust source containing test shapes for all affected schema elements
+- `run-test.sh`: Test runner script
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
similarity index 87%
rename from rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
rename to rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
index 1df9e112bbee..0616c973cb6d 100644
--- a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
@@ -1,6 +1,6 @@
 formatArgsArgName
-| upgrade_shapes.rs:22:37:22:41 | FormatArgsArg | upgrade_shapes.rs:22:37:22:37 | (no string representation) | upgrade_shapes.rs:22:41:22:41 | 1 | 37 |
-| upgrade_shapes.rs:22:44:22:48 | FormatArgsArg | upgrade_shapes.rs:22:44:22:44 | (no string representation) | upgrade_shapes.rs:22:48:22:48 | 2 | 44 |
+| upgrade_shapes.rs:22:37:22:41 | FormatArgsArg | upgrade_shapes.rs:22:13:22:49 | (no string representation) | upgrade_shapes.rs:22:41:22:41 | 1 | 13 |
+| upgrade_shapes.rs:22:44:22:48 | FormatArgsArg | upgrade_shapes.rs:22:13:22:49 | (no string representation) | upgrade_shapes.rs:22:48:22:48 | 2 | 13 |
 tryBlock
 | upgrade_shapes.rs:21:13:21:21 | { ... } |
 structFieldDefault
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.ql b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.ql
similarity index 100%
rename from rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.ql
rename to rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.ql
diff --git a/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.expected b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.expected
new file mode 100644
index 000000000000..441d08ab3c36
--- /dev/null
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.expected
@@ -0,0 +1,20 @@
+formatArgNamePreserved
+| upgrade_shapes.rs:22:37:22:41 | FormatArgsArg | upgrade_shapes.rs:22:37:22:39 | FormatArgsArgName | upgrade_shapes.rs:22:41:22:41 | 1 | 37 | 1 |
+| upgrade_shapes.rs:22:44:22:48 | FormatArgsArg | upgrade_shapes.rs:22:44:22:46 | FormatArgsArgName | upgrade_shapes.rs:22:48:22:48 | 2 | 44 | 2 |
+tryBlockModifierPreserved
+| upgrade_shapes.rs:21:13:21:21 | { ... } | upgrade_shapes.rs:21:13:21:15 | TryBlockModifier |
+structFieldDefaultPreserved
+| upgrade_shapes.rs:9:5:9:17 | field: u8 | upgrade_shapes.rs:9:17:9:17 | ConstArg | upgrade_shapes.rs:9:17:9:17 | 1 |
+variantDiscriminantPreserved
+| upgrade_shapes.rs:13:5:13:9 | V | upgrade_shapes.rs:13:9:13:9 | ConstArg | upgrade_shapes.rs:13:9:13:9 | 2 |
+pathMetaPreserved
+| upgrade_shapes.rs:4:3:4:11 | PathMeta | path_meta |
+| upgrade_shapes.rs:7:10:7:18 | PathMeta | path_meta |
+keyValueMetaPreserved
+| upgrade_shapes.rs:5:3:5:15 | KeyValueMeta | key_value | upgrade_shapes.rs:5:15:5:15 | 1 |
+tokenTreeMetaPreserved
+| upgrade_shapes.rs:6:3:6:18 | TokenTreeMeta | token_tree | upgrade_shapes.rs:6:13:6:18 | TokenTree |
+unsafeMetaPreserved
+| upgrade_shapes.rs:7:3:7:19 | UnsafeMeta | upgrade_shapes.rs:7:10:7:18 | PathMeta | path_meta |
+traitAliasPreserved
+| upgrade_shapes.rs:16:1:18:12 | trait Alias | upgrade_shapes.rs:16:7:16:11 | Alias | upgrade_shapes.rs:16:18:16:22 | ... | upgrade_shapes.rs:17:1:18:11 | WhereClause |
diff --git a/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.ql b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.ql
new file mode 100644
index 000000000000..bd983a8290c4
--- /dev/null
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.ql
@@ -0,0 +1,73 @@
+import codeql.rust.elements
+
+private predicate inUpgradeShapesFile(Locatable loc) {
+  loc.getFile().getBaseName() = "upgrade_shapes.rs"
+}
+
+query predicate formatArgNamePreserved(
+  FormatArgsArg arg, FormatArgsArgName argName, Expr expr, int argNameColumn, string exprText
+) {
+  inUpgradeShapesFile(arg) and
+  argName = arg.getArgName() and
+  expr = arg.getExpr() and
+  argNameColumn = argName.getLocation().getStartColumn() and
+  exprText = expr.toString()
+}
+
+query predicate tryBlockModifierPreserved(BlockExpr block, TryBlockModifier modifier) {
+  inUpgradeShapesFile(block) and
+  modifier = block.getTryBlockModifier() and
+  modifier.isTry() and
+  not modifier.hasTypeRepr()
+}
+
+query predicate structFieldDefaultPreserved(StructField field, ConstArg defaultVal, Expr expr) {
+  inUpgradeShapesFile(field) and
+  defaultVal = field.getDefaultVal() and
+  expr = defaultVal.getExpr()
+}
+
+query predicate variantDiscriminantPreserved(Variant variant, ConstArg constArg, Expr expr) {
+  inUpgradeShapesFile(variant) and
+  constArg = variant.getConstArg() and
+  expr = constArg.getExpr()
+}
+
+query predicate pathMetaPreserved(PathMeta meta, string pathText) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "path_meta"
+}
+
+query predicate keyValueMetaPreserved(KeyValueMeta meta, string pathText, Expr expr) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "key_value" and
+  expr = meta.getExpr()
+}
+
+query predicate tokenTreeMetaPreserved(TokenTreeMeta meta, string pathText, TokenTree tokenTree) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "token_tree" and
+  tokenTree = meta.getTokenTree()
+}
+
+query predicate unsafeMetaPreserved(UnsafeMeta meta, PathMeta inner, string pathText) {
+  inUpgradeShapesFile(meta) and
+  meta.isUnsafe() and
+  inner = meta.getMeta() and
+  pathText = inner.getPath().getText() and
+  pathText = "path_meta"
+}
+
+query predicate traitAliasPreserved(
+  Trait trait, Name name, TypeBoundList bounds, WhereClause whereClause
+) {
+  inUpgradeShapesFile(trait) and
+  name = trait.getName() and
+  name.getText() = "Alias" and
+  bounds = trait.getTypeBoundList() and
+  whereClause = trait.getWhereClause() and
+  not trait.hasAssocItemList()
+}
diff --git a/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
new file mode 100755
index 000000000000..48c78127bc5d
--- /dev/null
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
@@ -0,0 +1,65 @@
+#!/usr/bin/env bash
+# Manual regression test for the Rust dbscheme downgrade from rust-analyzer 0.0.328 to 0.0.301.
+# See README.md for details.
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_ROOT="$(git rev-parse --show-toplevel)"
+OLD_COMMIT="${OLD_COMMIT:-491c373e076}"  # origin/main at time of this upgrade
+OLD_DBSCHEME="rust/downgrades/109496fd2f20f28a35e50b110859e74882ee80d6/rust.dbscheme"
+
+cd "$REPO_ROOT"
+
+if ! git diff --quiet HEAD || [ -n "$(git ls-files --others --exclude-standard)" ]; then
+    echo "ERROR: Working directory has uncommitted changes." >&2
+    echo "Please commit or stash your changes before running this test." >&2
+    exit 1
+fi
+
+ORIGINAL_REF="$(git rev-parse --abbrev-ref HEAD)"
+if [ "$ORIGINAL_REF" = "HEAD" ]; then
+    ORIGINAL_REF="$(git rev-parse HEAD)"
+fi
+
+restore_ref() {
+    echo "==> Restoring original ref ($ORIGINAL_REF)..."
+    git checkout --quiet "$ORIGINAL_REF"
+}
+trap 'restore_ref' EXIT
+
+echo "==> Building current extractor (this may take a while)..."
+bazel run //rust:install
+
+echo "==> Creating new-schema test database..."
+codeql test run \
+    --search-path . \
+    --keep-databases \
+    "$SCRIPT_DIR/new.ql" "$@"
+
+echo "==> Downgrading dataset to old schema..."
+DATASET_DIR=("$SCRIPT_DIR"/*.testproj/db-rust)
+if [[ ! -d "${DATASET_DIR[0]}" ]]; then
+    echo "ERROR: No testproj found at $SCRIPT_DIR/*.testproj" >&2
+    exit 1
+fi
+codeql dataset upgrade "${DATASET_DIR[0]}" \
+    --allow-downgrades \
+    --search-path rust \
+    --target-dbscheme "$OLD_DBSCHEME"
+
+echo "==> Checking out old commit ($OLD_COMMIT) for downgrade verification..."
+git checkout --quiet "$OLD_COMMIT"
+git checkout --quiet "$ORIGINAL_REF" -- rust/ql/downgrade-tests codeql-workspace.yml
+
+echo "==> Running preservation test on downgraded dataset..."
+codeql test run \
+    --search-path . \
+    --dataset "${DATASET_DIR[0]}" \
+    --check-databases \
+    "$SCRIPT_DIR/downgraded.ql" "$@"
+
+restore_ref
+trap '' EXIT
+
+echo "==> All tests passed!"
diff --git a/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/upgrade_shapes.rs b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/upgrade_shapes.rs
new file mode 100644
index 000000000000..e64d8f6582c6
--- /dev/null
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/upgrade_shapes.rs
@@ -0,0 +1,23 @@
+#![allow(dead_code)]
+#![feature(more_qualified_paths)]
+
+#[path_meta]
+#[key_value = 1]
+#[token_tree(list)]
+#[unsafe(path_meta)]
+struct S {
+    field: u8 = 1,
+}
+
+enum E {
+    V = 2,
+}
+
+trait Alias<T> = Clone
+where
+    T: Copy;
+
+fn f() {
+    let _ = try { 1 };
+    let _ = format_args!("{b} {a}", a = 1, b = 2);
+}
diff --git a/rust/ql/downgrade-tests/qlpack.yml b/rust/ql/downgrade-tests/qlpack.yml
new file mode 100644
index 000000000000..e2e42acf460f
--- /dev/null
+++ b/rust/ql/downgrade-tests/qlpack.yml
@@ -0,0 +1,5 @@
+name: codeql/rust-downgrade-tests
+version: 0.0.0
+extractor: rust
+dependencies:
+  codeql/rust-all: ${workspace}
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
index 3b4d77eb40d2..1abb3d60e268 100644
--- a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
@@ -1,3 +1,5 @@
 *.testproj/
 *.actual
 *.log
+Cargo.toml
+lib.rs
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
index a728458bef42..ecc94261ee51 100644
--- a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
@@ -1,6 +1,6 @@
 # Upgrade Regression Test for rust-analyzer 0.0.301 → 0.0.328
 
-This test verifies that the dbscheme upgrade and downgrade scripts correctly preserve data when migrating databases between the old and new schemas.
+This test verifies that the dbscheme upgrade script correctly preserves data when migrating databases from the old schema to the new schema.
 
 ## Running the test
 
@@ -16,13 +16,10 @@ This will:
 5. Restore your branch
 6. Upgrade the database to the new schema
 7. Verify that the old properties are still accessible via the new schema
-8. Downgrade the database back to the old schema
-9. Verify that the recovered old-schema properties still match
 
 ## Files
 
-- `old.ql` / `old.expected`: Query for the old schema (validates extraction and downgrade)
+- `old.ql` / `old.expected`: Query for the old schema (validates extraction)
 - `new.ql` / `new.expected`: Query for the new schema (validates upgrade preserved data)
-- `downgraded.ql` / `downgraded.expected`: Query for the downgraded old schema
 - `upgrade_shapes.rs`: Rust source containing test shapes for all affected schema elements
 - `run-test.sh`: Test runner script
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
index 1dbbf2783b7a..b5ae0d8a42f7 100755
--- a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
@@ -7,7 +7,6 @@ set -euo pipefail
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 REPO_ROOT="$(git rev-parse --show-toplevel)"
 OLD_COMMIT="${OLD_COMMIT:-491c373e076}"  # origin/main at time of this upgrade
-OLD_DBSCHEME="rust/downgrades/109496fd2f20f28a35e50b110859e74882ee80d6/rust.dbscheme"
 
 cd "$REPO_ROOT"
 
@@ -65,26 +64,4 @@ codeql test run \
     --check-databases \
     "$SCRIPT_DIR/new.ql" "$@"
 
-echo "==> Downgrading dataset back to old schema..."
-codeql dataset upgrade "${DATASET_DIR[0]}" \
-    --allow-downgrades \
-    --search-path rust \
-    --target-dbscheme "$OLD_DBSCHEME"
-
-trap 'restore_ref' EXIT
-
-echo "==> Checking out old commit ($OLD_COMMIT) for downgrade verification..."
-git checkout --quiet "$OLD_COMMIT"
-git checkout --quiet "$ORIGINAL_REF" -- rust/ql/upgrade-tests codeql-workspace.yml
-
-echo "==> Running preservation test on downgraded dataset..."
-codeql test run \
-    --search-path . \
-    --dataset "${DATASET_DIR[0]}" \
-    --check-databases \
-    "$SCRIPT_DIR/downgraded.ql" "$@"
-
-restore_ref
-trap '' EXIT
-
 echo "==> All tests passed!"