Fix #74 Improve handling of embedded comments in semantic tokens

The algorithm will no longer loop infinitely when encountering embedded comments in ARG or ENV instructions. Signed-off-by: Remy Suen <[email protected]>
rcjsuen · Apr 10, 2021 · 29d560a · 29d560a
1 parent ce25ab8
commit 29d560a
Show file tree

Hide file tree

Showing 3 changed files with 31 additions and 1 deletion.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -7,6 +7,7 @@ All notable changes to this project will be documented in this file.
 
 ### Fixed
 - do not validate variable substitutions if found in CMD and ENTRYPOINT ([rcjsuen/dockerfile-utils#89](https://github.com/rcjsuen/dockerfile-utils/issues/89))
+- fix infinite loop issue when calculating semantic tokens for ARG or ENV instructions with nested comments ([#74](https://github.com/rcjsuen/dockerfile-language-service/issues/74))
 
 ## [0.2.0] - 2021-01-20
 ### Added

diff --git a/src/dockerSemanticTokens.ts b/src/dockerSemanticTokens.ts
@@ -426,6 +426,7 @@ export class DockerSemanticTokens {
                 switch (ch) {
                     case '#':
                         if (escaping) {
+                            let commenting = true;
                             commentCheck: for (let j = i + 1; j < endOffset; j++) {
                                 switch (this.content.charAt(j)) {
                                     case ' ':
@@ -439,7 +440,9 @@ export class DockerSemanticTokens {
                                         this.createToken(null, crComment, SemanticTokenTypes.comment, [], false);
                                         i = j + 1;
                                         startOffset = -1;
-                                        break commentCheck;
+                                        commenting = false;
+                                        j++;
+                                        break;
                                     case '\n':
                                         const lfComment = {
                                             start: this.document.positionAt(i),
@@ -448,6 +451,19 @@ export class DockerSemanticTokens {
                                         this.createToken(null, lfComment, SemanticTokenTypes.comment, [], false);
                                         i = j;
                                         startOffset = -1;
+                                        commenting = false;
+                                        break;
+                                    case '#':
+                                        if (!commenting) {
+                                            i = j;
+                                        }
+                                        commenting = true;
+                                        break;
+                                    default:
+                                        if (commenting) {
+                                            break;
+                                        }
+                                        i = j - 1;
                                         break commentCheck;
                                 }
                             }

diff --git a/test/dockerSemanticTokens.test.ts b/test/dockerSemanticTokens.test.ts
@@ -88,6 +88,19 @@ describe("Dockerfile Semantic Token tests", () => {
                         assertEdit(tokens.data, SemanticTokenTypes.parameter, 20, 0, 7, 23);
                         assertEdit(tokens.data, SemanticTokenTypes.variable, 25, 0, 23, 5);
                     });
+
+                    it(keyword + " a \\\\n b \\\\n # comment\\n # comment\\n c", () => {
+                        const tokens = computeSemanticTokens(keyword + " a \\\n b \\\n # comment\n # comment\n c");
+                        assert.equal(40, tokens.data.length);
+                        assertEdit(tokens.data, SemanticTokenTypes.keyword, 0, 0, 0, keyword.length);
+                        assertEdit(tokens.data, SemanticTokenTypes.variable, 5, 0, keyword.length + 1, 1, [SemanticTokenModifiers.declaration]);
+                        assertEdit(tokens.data, SemanticTokenTypes.macro, 10, 0, 2, 1);
+                        assertEdit(tokens.data, SemanticTokenTypes.parameter, 15, 1, 1, 2);
+                        assertEdit(tokens.data, SemanticTokenTypes.macro, 20, 0, 2, 1);
+                        assertEdit(tokens.data, SemanticTokenTypes.comment, 25, 1, 1, 9);
+                        assertEdit(tokens.data, SemanticTokenTypes.comment, 30, 1, 1, 9);
+                        assertEdit(tokens.data, SemanticTokenTypes.parameter, 35, 1, 1, 1);
+                    });
                 });
             }
             createVariableDeclarationTests("ARG");