From 70621d4b8cf35f6cbbde89447477b9f4286427e1 Mon Sep 17 00:00:00 2001
From: Dominic Nguyen <datnguyen5653@gmail.com>
Date: Mon, 20 Jul 2026 22:13:27 -0700
Subject: [PATCH] Fix short flag value detection

- Reject unquoted short flags when a value-taking flag is missing its value.

- Preserve negative numeric strings and quoted flag-like values.

- Add focused parser regression coverage.
---
 .../dispatcher/src/command/parameters.ts      |  4 +--
 .../dispatcher/dispatcher/test/flags.spec.ts  | 28 +++++++++++++++++++
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/ts/packages/dispatcher/dispatcher/src/command/parameters.ts b/ts/packages/dispatcher/dispatcher/src/command/parameters.ts
index 8b96acab90..261d52b49b 100644
--- a/ts/packages/dispatcher/dispatcher/src/command/parameters.ts
+++ b/ts/packages/dispatcher/dispatcher/src/command/parameters.ts
@@ -85,8 +85,8 @@ function invalidValueToken(valueToken: string) {
     if (
         valueToken.length === 2 &&
         valueToken[0] === "-" &&
-        valueToken.charCodeAt(1) < 48 /* "0" */ &&
-        valueToken.charCodeAt(1) > 57 /* "9" */
+        (valueToken.charCodeAt(1) < 48 /* "0" */ ||
+            valueToken.charCodeAt(1) > 57) /* "9" */
     ) {
         return true;
     }
diff --git a/ts/packages/dispatcher/dispatcher/test/flags.spec.ts b/ts/packages/dispatcher/dispatcher/test/flags.spec.ts
index 509536b1cf..cf92be231e 100644
--- a/ts/packages/dispatcher/dispatcher/test/flags.spec.ts
+++ b/ts/packages/dispatcher/dispatcher/test/flags.spec.ts
@@ -13,6 +13,20 @@ describe("Flag parsing", () => {
             obj: { description: "testing", type: "json" },
         },
     } as const;
+    const shortFlags = {
+        flags: {
+            output: {
+                description: "output",
+                type: "string",
+                char: "o",
+            },
+            verbose: {
+                description: "verbose",
+                type: "boolean",
+                char: "v",
+            },
+        },
+    } as const;
     const o1 = { hello: "str", num: 11, bool: true };
     const o2 = { ...o1, obj: o1, arr: [o1, o1] };
     it("type", () => {
@@ -257,6 +271,20 @@ describe("Flag parsing", () => {
         }
     });
 
+    it("does not consume a following short flag as a string value", () => {
+        expect(() => parseParams("-o -v", shortFlags)).toThrow(
+            "Missing value for flag '-o'",
+        );
+    });
+
+    it("accepts a negative numeric-looking string as a short flag value", () => {
+        expect(parseParams("-o -1", shortFlags).flags.output).toBe("-1");
+    });
+
+    it("accepts a quoted short-flag-looking string as a short flag value", () => {
+        expect(parseParams("-o '-v'", shortFlags).flags.output).toBe("-v");
+    });
+
     it("Duplicate flags", () => {
         try {
             parseParams("--num 10 --num 11", typeFlags);