feat: map known code block languages to respective file extensions

eslint · Mar 27, 2024 · e40891f · e40891f
1 parent bb5c3d4
commit e40891f
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Showing 2 changed files with 39 additions and 14 deletions.
diff --git a/lib/processor.js b/lib/processor.js
@@ -235,6 +235,14 @@ function getBlockRangeMap(text, node, comments) {
     return rangeMap;
 }
 
+const languageToFileExtension = {
+    javascript: "js",
+    node: "js",
+    ecmascript: "js",
+    typescript: "ts",
+    markdown: "md"
+};
+
 /**
  * Extracts lintable code blocks from Markdown text.
  * @param {string} text The text of the file.
@@ -295,14 +303,19 @@ function preprocess(text, filename) {
         }
     });
 
-    return blocks.map((block, index) => ({
-        filename: `${index}.${block.lang.trim().split(" ")[0]}`,
-        text: [
-            ...block.comments,
-            block.value,
-            ""
-        ].join("\n")
-    }));
+    return blocks.map((block, index) => {
+        const [language] = block.lang.trim().split(" ");
+        const fileExtension = Object.hasOwn(languageToFileExtension, language) ? languageToFileExtension[language] : language;
+
+        return {
+            filename: `${index}.${fileExtension}`,
+            text: [
+                ...block.comments,
+                block.value,
+                ""
+            ].join("\n")
+        };
+    });
 }
 
 /**

diff --git a/tests/lib/processor.js b/tests/lib/processor.js
@@ -115,7 +115,7 @@ describe("processor", () => {
                 "```js",
                 "backticks",
                 "```",
-                "~~~javascript",
+                "~~~js",
                 "tildes",
                 "~~~"
             ].join("\n");
@@ -124,7 +124,7 @@ describe("processor", () => {
             assert.strictEqual(blocks.length, 2);
             assert.strictEqual(blocks[0].filename, "0.js");
             assert.strictEqual(blocks[0].text, "backticks\n");
-            assert.strictEqual(blocks[1].filename, "1.javascript");
+            assert.strictEqual(blocks[1].filename, "1.js");
             assert.strictEqual(blocks[1].text, "tildes\n");
         });
 
@@ -255,7 +255,7 @@ describe("processor", () => {
             const blocks = processor.preprocess(code);
 
             assert.strictEqual(blocks.length, 1);
-            assert.strictEqual(blocks[0].filename, "0.javascript");
+            assert.strictEqual(blocks[0].filename, "0.js");
         });
 
         it("should find code fences with node info string", () => {
@@ -267,7 +267,7 @@ describe("processor", () => {
             const blocks = processor.preprocess(code);
 
             assert.strictEqual(blocks.length, 1);
-            assert.strictEqual(blocks[0].filename, "0.node");
+            assert.strictEqual(blocks[0].filename, "0.js");
         });
 
         it("should find code fences with jsx info string", () => {
@@ -330,6 +330,18 @@ describe("processor", () => {
             assert.strictEqual(blocks[0].filename, "0.js");
         });
 
+        it("should the language to its file extension with leading whitespace and trailing characters", () => {
+            const code = [
+                "```   javascript  CUSTOM",
+                "var answer = 6 * 7;",
+                "```"
+            ].join("\n");
+            const blocks = processor.preprocess(code);
+
+            assert.strictEqual(blocks.length, 1);
+            assert.strictEqual(blocks[0].filename, "0.js");
+        });
+
         it("should find code fences not surrounded by blank lines", () => {
             const code = [
                 "<!-- eslint-disable -->",
@@ -408,7 +420,7 @@ describe("processor", () => {
                 "var answer = 6 * 7;",
                 "```",
                 "",
-                "```javascript",
+                "```js",
                 "console.log(answer);",
                 "```",
                 "",
@@ -419,7 +431,7 @@ describe("processor", () => {
             assert.strictEqual(blocks.length, 2);
             assert.strictEqual(blocks[0].filename, "0.js");
             assert.strictEqual(blocks[0].text, "var answer = 6 * 7;\n");
-            assert.strictEqual(blocks[1].filename, "1.javascript");
+            assert.strictEqual(blocks[1].filename, "1.js");
             assert.strictEqual(blocks[1].text, "console.log(answer);\n");
         });