Fix bug where variable renaming would fail to update all occurrences of the variable in the presence of character code notation (0'Char)

Author: pmoura

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## [0.85.4]
+
+* Fix bug where variable renaming would fail to update all occurrences of the variable in the presence of character code notation (0'Char)
+
 ## [0.85.3]
 
 * Fix bug where predicate/non-terminal argument refactoring would fail to update all clauses/rules

package.json

@@ -2,7 +2,7 @@
     "name": "logtalk-for-vscode",
     "displayName": "Logtalk for VSCode",
     "description": "Logtalk programming support",
-    "version": "0.85.3",
+    "version": "0.85.4",
     "publisher": "LogtalkDotOrg",
     "icon": "images/logtalk.png",
     "license": "MIT",
@@ -1338,7 +1338,7 @@
         "compile": "tsc -watch -p ./",
         "test": "tsc ./tests/runTest.ts",
         "vsix:make": "vsce package --baseImagesUrl https://raw.githubusercontent.com/llvm/llvm-project/master/clang-tools-extra/clangd/clients/clangd-vscode/",
-        "vsix:install": "code --install-extension logtalk-for-vscode-0.85.3.vsix"
+        "vsix:install": "code --install-extension logtalk-for-vscode-0.85.4.vsix"
     },
     "devDependencies": {
         "@types/bluebird": "^3.5.38",

src/features/renameProvider.ts

@@ -71,8 +71,9 @@ export class LogtalkRenameProvider implements RenameProvider {
     }
 
     // Check if we're in a string literal
+    // Use the helper method that properly handles character code notation (0'Char)
     const beforeCursor = lineText.substring(0, position.character);
-    const singleQuotes = (beforeCursor.match(/'/g) || []).length;
+    const singleQuotes = this.countSingleQuotesExcludingCharCodes(beforeCursor);
     const doubleQuotes = (beforeCursor.match(/"/g) || []).length;
     if (singleQuotes % 2 !== 0 || doubleQuotes % 2 !== 0) {
       return null;
@@ -932,6 +933,35 @@ export class LogtalkRenameProvider implements RenameProvider {
     return workspaceEdit;
   }
 
+  /**
+   * Counts single quotes in a string, excluding those that are part of character code notation (0'Char)
+   * @param text The text to count quotes in
+   * @returns The count of single quotes that are not part of character code notation
+   */
+  private countSingleQuotesExcludingCharCodes(text: string): number {
+    let count = 0;
+    for (let i = 0; i < text.length; i++) {
+      if (text[i] === "'") {
+        // Check if this quote is part of character code notation (preceded by '0')
+        if (i > 0 && text[i - 1] === '0') {
+          // This is character code notation like 0'x, skip this quote
+          // Also skip the next character (the char being represented)
+          if (i + 1 < text.length) {
+            // Handle escape sequences like 0'\n, 0'\\, etc.
+            if (text[i + 1] === '\\' && i + 2 < text.length) {
+              i += 2; // Skip the backslash and the escaped character
+            } else {
+              i += 1; // Skip the single character
+            }
+          }
+        } else {
+          count++;
+        }
+      }
+    }
+    return count;
+  }
+
   /**
    * Validates if a variable occurrence is in a valid context (not in string)
    * Note: We DO want to rename variables in comments to keep them accurate
@@ -943,7 +973,7 @@ export class LogtalkRenameProvider implements RenameProvider {
   private isValidVariableContextInLine(lineText: string, startPos: number, endPos: number): boolean {
     // Check if this is in a string literal
     const beforeMatch = lineText.substring(0, startPos);
-    const singleQuotes = (beforeMatch.match(/'/g) || []).length;
+    const singleQuotes = this.countSingleQuotesExcludingCharCodes(beforeMatch);
     const doubleQuotes = (beforeMatch.match(/"/g) || []).length;
     if (singleQuotes % 2 !== 0 || doubleQuotes % 2 !== 0) {
       return false;

tests/renameProvider.test.ts

@@ -307,4 +307,60 @@ suite('LogtalkRenameProvider Test Suite', () => {
     // Should NOT find 'member(+term, ?list)' because it's looking for indicator format
     assert.strictEqual(ranges.length, 0);
   });
+
+  // Tests for character code notation handling (0'Char)
+  test('countSingleQuotesExcludingCharCodes - no quotes', () => {
+    const count = (renameProvider as any).countSingleQuotesExcludingCharCodes('hello world');
+    assert.strictEqual(count, 0);
+  });
+
+  test('countSingleQuotesExcludingCharCodes - regular quoted atom', () => {
+    const count = (renameProvider as any).countSingleQuotesExcludingCharCodes("'hello'");
+    assert.strictEqual(count, 2);
+  });
+
+  test('countSingleQuotesExcludingCharCodes - character code notation 0\'0', () => {
+    // Character code notation should not count the quote
+    const count = (renameProvider as any).countSingleQuotesExcludingCharCodes("Code >= 0'0, Code =< 0'9");
+    assert.strictEqual(count, 0);
+  });
+
+  test('countSingleQuotesExcludingCharCodes - character code with escape sequence', () => {
+    // Character code with escape like 0'\n should not count the quote
+    const count = (renameProvider as any).countSingleQuotesExcludingCharCodes("Code = 0'\\n");
+    assert.strictEqual(count, 0);
+  });
+
+  test('countSingleQuotesExcludingCharCodes - mixed quotes and char codes', () => {
+    // Mix of quoted atoms and character codes
+    const count = (renameProvider as any).countSingleQuotesExcludingCharCodes("'atom', 0'x, 'another'");
+    assert.strictEqual(count, 4); // 2 for 'atom' + 2 for 'another', 0 for 0'x
+  });
+
+  test('isValidVariableContextInLine - variable after character code notation', () => {
+    // Variable Code after 0'0 should be in valid context (not inside quotes)
+    const isValid = (renameProvider as any).isValidVariableContextInLine(
+      "hex_digit(Code, Value) :- Code >= 0'0, Code =< 0'9, !, Value is Code - 0'0.",
+      61, 65 // Position of the last "Code" before "- 0'0"
+    );
+    assert.strictEqual(isValid, true);
+  });
+
+  test('isValidVariableContextInLine - variable between character codes', () => {
+    // Variable Code between 0'0 and 0'9 should be in valid context
+    const isValid = (renameProvider as any).isValidVariableContextInLine(
+      "hex_digit(Code, Value) :- Code >= 0'0, Code =< 0'9, !, Value is Code - 0'0.",
+      39, 43 // Position of "Code" in "Code =< 0'9"
+    );
+    assert.strictEqual(isValid, true);
+  });
+
+  test('isValidVariableContextInLine - variable inside actual quoted atom should be invalid', () => {
+    // Variable inside a quoted atom should not be valid
+    const isValid = (renameProvider as any).isValidVariableContextInLine(
+      "test('Code is here', Code).",
+      6, 10 // Position of "Code" inside the quoted atom
+    );
+    assert.strictEqual(isValid, false);
+  });
 });

tests/variable-rename-test.lgt

@@ -96,5 +96,27 @@
         % Value is a test variable
         write(Value). % Print Value
 
+    % Test 16: Variable with character code notation (0'Char)
+    % All occurrences of Code should be renamed, not just the first two
+    % The single quotes in 0'0 and 0'9 are character code notation, not quoted atoms
+    hex_digit(Code, Value) :-
+        Code >= 0'0,
+        Code =< 0'9,
+        !,
+        Value is Code - 0'0.
+
+    % Test 17: Multiple character codes in same clause
+    is_ascii_letter(Code) :-
+        (   Code >= 0'a, Code =< 0'z
+        ;   Code >= 0'A, Code =< 0'Z
+        ).
+
+    % Test 18: Character code with escape sequences
+    is_whitespace(Code) :-
+        (   Code = 0'
+        ;   Code = 0'\t
+        ;   Code = 0'\n
+        ).
+
 :- end_object.