fix: restrict @-mention parsing to line-start or whitespace boundaries (#7876)

Co-authored-by: Roo Code <roomote@roocode.com>

src/shared/__tests__/context-mentions.spec.ts

@@ -3,37 +3,55 @@ import { mentionRegex, mentionRegexGlobal } from "../context-mentions"
 describe("mentionRegex and mentionRegexGlobal", () => {
 	// Test cases for various mention types
 	const testCases = [
-		// Basic file paths
+		// Basic file paths at line start
 		{ input: "@/path/to/file.txt", expected: ["@/path/to/file.txt"] },
 		{ input: "@/file.js", expected: ["@/file.js"] },
 		{ input: "@/folder/", expected: ["@/folder/"] },
 
-		// File paths with escaped spaces
+		// File paths with escaped spaces at line start
 		{ input: "@/path/to/file\\ with\\ spaces.txt", expected: ["@/path/to/file\\ with\\ spaces.txt"] },
 		{ input: "@/users/my\\ project/report\\ final.pdf", expected: ["@/users/my\\ project/report\\ final.pdf"] },
 		{ input: "@/folder\\ with\\ spaces/", expected: ["@/folder\\ with\\ spaces/"] },
 		{ input: "@/a\\ b\\ c.txt", expected: ["@/a\\ b\\ c.txt"] },
 
-		// URLs
+		// URLs at line start
 		{ input: "@http://example.com", expected: ["@http://example.com"] },
 		{ input: "@https://example.com/path?query=1", expected: ["@https://example.com/path?query=1"] },
 
-		// Other mentions
+		// Other mentions at line start
 		{ input: "@problems", expected: ["@problems"] },
 		{ input: "@git-changes", expected: ["@git-changes"] },
 		{ input: "@terminal", expected: ["@terminal"] },
 		{ input: "@a1b2c3d", expected: ["@a1b2c3d"] }, // Git commit hash (short)
 		{ input: "@a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0", expected: ["@a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0"] }, // Git commit hash (long)
 
-		// Mentions within text
+		// Mentions after whitespace (valid)
 		{
 			input: "Check file @/path/to/file\\ with\\ spaces.txt for details.",
 			expected: ["@/path/to/file\\ with\\ spaces.txt"],
 		},
 		{ input: "See @problems and @terminal output.", expected: ["@problems", "@terminal"] },
-		{ input: "URL: @https://example.com.", expected: ["@https://example.com"] }, // Trailing punctuation
+		{ input: "URL: @https://example.com.", expected: ["@https://example.com"] }, // After colon and space
 		{ input: "Commit @a1b2c3d, then check @/file.txt", expected: ["@a1b2c3d", "@/file.txt"] },
 
+		// NEW: Test cases for mentions mid-line without whitespace (should NOT match)
+		{ input: "error@https://example.com/path", expected: null }, // @ mid-word before URL
+		{ input: "log:@/var/log/system.log", expected: null }, // @ after colon without space
+		{ input: "email@problems", expected: null }, // @ mid-word before "problems"
+		{ input: "path=@/usr/local/bin", expected: null }, // @ after equals without space
+		{ input: "Error at line 42@terminal output", expected: null }, // @ mid-line before "terminal"
+		{ input: "commit@a1b2c3d", expected: null }, // @ mid-word before git hash
+
+		// NEW: Test cases for pasted logs (should NOT match)
+		{ input: "Failed to fetch@https://api.example.com/endpoint", expected: null },
+		{ input: "Error loading resource@/assets/image.png", expected: null },
+		{ input: "Stack trace:@/home/user/project/file.js:42", expected: null },
+
+		// NEW: Valid mentions with various whitespace
+		{ input: "Check\t@/path/to/file.txt", expected: ["@/path/to/file.txt"] }, // Tab before @
+		{ input: "Multiple  @problems here", expected: ["@problems"] }, // Multiple spaces
+		{ input: "Newline\n@terminal output", expected: ["@terminal"] }, // After newline
+
 		// Negative cases (should not match or match partially)
 		{ input: "@/path/with unescaped space.txt", expected: ["@/path/with"] }, // Unescaped space
 		{ input: "@ /path/leading-space.txt", expected: null }, // Space after @
@@ -41,14 +59,15 @@ describe("mentionRegex and mentionRegexGlobal", () => {
 		{ input: "mention@", expected: null }, // Trailing @
 		{ input: "@/path/trailing\\", expected: null }, // Trailing backslash (invalid escape)
 		{ input: "@/path/to/file\\not-a-space", expected: null }, // Backslash not followed by space
+
 		// Escaped mentions (should not match due to negative lookbehind)
 		{ input: "This is not a mention: \\@/path/to/file.txt", expected: null },
 		{ input: "Escaped \\@problems word", expected: null },
 		{ input: "Text with \\@https://example.com", expected: null },
 		{ input: "Another \\@a1b2c3d hash", expected: null },
-		{ input: "Not escaped @terminal", expected: ["@terminal"] }, // Ensure non-escaped still works nearby
-		{ input: "Double escape \\\\@/should/match", expected: null }, // Double backslash escapes the backslash, currently incorrectly fails to match
-		{ input: "Text with \\@/escaped/path\\ with\\ spaces.txt", expected: null }, // Escaped mention with escaped spaces within the path part
+		{ input: "Not escaped @terminal", expected: ["@terminal"] }, // After space, should work
+		{ input: "Double escape \\\\@/should/match", expected: null }, // Double backslash escapes the backslash
+		{ input: "Text with \\@/escaped/path\\ with\\ spaces.txt", expected: null }, // Escaped mention with escaped spaces
 	]
 	testCases.forEach(({ input, expected }) => {
 		it(`should handle input: "${input}"`, () => {
@@ -83,4 +102,48 @@ describe("mentionRegex and mentionRegexGlobal", () => {
 		expect(matches[0][1]).toBe("/path/to/escaped\\ file.txt") // Group 1 should not include '@'
 		expect(matches[1][1]).toBe("problems")
 	})
+
+	// NEW: Additional tests for the boundary restriction
+	describe("boundary restrictions", () => {
+		it("should match mentions at the start of a line", () => {
+			const input = "@/path/to/file.txt"
+			const match = input.match(mentionRegex)
+			expect(match).not.toBeNull()
+			expect(match?.[0]).toBe("@/path/to/file.txt")
+		})
+
+		it("should match mentions after whitespace", () => {
+			const input = "Check @/path/to/file.txt"
+			const match = input.match(mentionRegex)
+			expect(match).not.toBeNull()
+			expect(match?.[0]).toBe("@/path/to/file.txt")
+		})
+
+		it("should NOT match mentions mid-word or after non-whitespace", () => {
+			const testCases = ["error@https://example.com", "path:@/var/log", "email@problems", "42@terminal"]
+
+			testCases.forEach((input) => {
+				const match = input.match(mentionRegex)
+				expect(match).toBeNull()
+			})
+		})
+
+		it("should handle multiline text correctly", () => {
+			const input = `First line
+@/path/on/newline.txt
+Mid-line@/should/not/match.txt
+After space @/should/match.txt`
+
+			const matches = Array.from(input.matchAll(mentionRegexGlobal))
+			expect(matches.length).toBe(2)
+			expect(matches[0][0]).toBe("@/path/on/newline.txt")
+			expect(matches[1][0]).toBe("@/should/match.txt")
+		})
+
+		it("should not match mentions in pasted log entries", () => {
+			const logEntry = "Error: Failed to load resource@https://api.example.com/data status:404"
+			const matches = Array.from(logEntry.matchAll(mentionRegexGlobal))
+			expect(matches.length).toBe(0)
+		})
+	})
 })

src/shared/context-mentions.ts

@@ -1,19 +1,25 @@
 /*
 Mention regex:
-- **Purpose**: 
-  - To identify and highlight specific mentions in text that start with '@'. 
+- **Purpose**:
+  - To identify and highlight specific mentions in text that start with '@'.
   - These mentions can be file paths, URLs, or the exact word 'problems'.
   - Ensures that trailing punctuation marks (like commas, periods, etc.) are not included in the match, allowing punctuation to follow the mention without being part of it.
+  - Restricts @ parsing to line-start or after whitespace to avoid accidental loading from pasted logs.
 
 - **Regex Breakdown**:
-  - `/@`: 
+  - `(?:^|\s)`:
+	- **Non-Capturing Group (`(?:...)`)**: Groups the alternatives without capturing them.
+	- **Line Start or Whitespace (`^|\s`)**: The @ must be at the start of a line or preceded by whitespace.
+  
+  - `(?<!\\)@`:
+	- **Negative Lookbehind (`(?<!\\)`)**: Ensures the @ is not escaped with a backslash.
 	- **@**: The mention must start with the '@' symbol.
   
   - `((?:\/|\w+:\/\/)[^\s]+?|problems\b|git-changes\b)`:
 	- **Capturing Group (`(...)`)**: Captures the part of the string that matches one of the specified patterns.
-	- `(?:\/|\w+:\/\/)`: 
+	- `(?:\/|\w+:\/\/)`:
 	  - **Non-Capturing Group (`(?:...)`)**: Groups the alternatives without capturing them for back-referencing.
-	  - `\/`: 
+	  - `\/`:
 		- **Slash (`/`)**: Indicates that the mention is a file or folder path starting with a '/'.
 	  - `|`: Logical OR.
 	  - `\w+:\/\/`:
@@ -25,7 +31,7 @@ Mention regex:
 	  - **Escaped Space (`\\ `)**: Matches a backslash followed by a space (an escaped space).
 	  - **Non-Greedy (`+?`)**: Ensures the smallest possible match, preventing the inclusion of trailing punctuation.
 	- `|`: Logical OR.
-	- `problems\b`: 
+	- `problems\b`:
 	  - **Exact Word ('problems')**: Matches the exact word 'problems'.
 	  - **Word Boundary (`\b`)**: Ensures that 'problems' is matched as a whole word and not as part of another word (e.g., 'problematic').
 		- `|`: Logical OR.
@@ -34,9 +40,9 @@ Mention regex:
       - **Word Boundary (`\b`)**: Ensures that 'terminal' is matched as a whole word and not as part of another word (e.g., 'terminals').
   - `(?=[.,;:!?]?(?=[\s\r\n]|$))`:
 	- **Positive Lookahead (`(?=...)`)**: Ensures that the match is followed by specific patterns without including them in the match.
-	- `[.,;:!?]?`: 
+	- `[.,;:!?]?`:
 	  - **Optional Punctuation (`[.,;:!?]?`)**: Matches zero or one of the specified punctuation marks.
-	- `(?=[\s\r\n]|$)`: 
+	- `(?=[\s\r\n]|$)`:
 	  - **Nested Positive Lookahead (`(?=[\s\r\n]|$)`)**: Ensures that the punctuation (if present) is followed by a whitespace character, a line break, or the end of the string.
   
 - **Summary**:
@@ -48,13 +54,14 @@ Mention regex:
 	- The exact word 'git-changes'.
     - The exact word 'terminal'.
   - It ensures that any trailing punctuation marks (such as ',', '.', '!', etc.) are not included in the matched mention, allowing the punctuation to follow the mention naturally in the text.
+  - **NEW**: The @ symbol must be at the start of a line or preceded by whitespace to prevent accidental matches in pasted logs.
 
 - **Global Regex**:
   - `mentionRegexGlobal`: Creates a global version of the `mentionRegex` to find all matches within a given string.
 
 */
 export const mentionRegex =
-	/(?<!\\)@((?:\/|\w+:\/\/)(?:[^\s\\]|\\ )+?|[a-f0-9]{7,40}\b|problems\b|git-changes\b|terminal\b)(?=[.,;:!?]?(?=[\s\r\n]|$))/
+	/(?:^|(?<=\s))(?<!\\)@((?:\/|\w+:\/\/)(?:[^\s\\]|\\ )+?|[a-f0-9]{7,40}\b|problems\b|git-changes\b|terminal\b)(?=[.,;:!?]?(?=[\s\r\n]|$))/
 export const mentionRegexGlobal = new RegExp(mentionRegex.source, "g")
 
 // Regex to match command mentions like /command-name anywhere in text