prettier · azz · Oct 11, 2017 · Sep 21, 2017 · Sep 21, 2017 · Sep 21, 2017
diff --git a/.gitignore b/.gitignore
@@ -1,5 +1,5 @@
 /node_modules
-npm-debug.log
+*.log
 /errors
 /test.js
 /test.ts

diff --git a/package.json b/package.json
@@ -21,6 +21,7 @@
     "cosmiconfig": "3.1.0",
     "dashify": "0.2.2",
     "diff": "3.2.0",
+    "escape-string-regexp": "1.0.5",
     "esutils": "2.0.2",
     "flow-parser": "0.51.0",
     "get-stream": "3.0.0",
@@ -39,9 +40,12 @@
     "postcss-scss": "1.0.0",
     "postcss-selector-parser": "2.2.3",
     "postcss-values-parser": "1.3.1",
+    "remark-frontmatter": "1.1.0",
+    "remark-parse": "4.0.0",
     "strip-bom": "3.0.0",
     "typescript": "2.5.3",
-    "typescript-eslint-parser": "git://github.com/eslint/typescript-eslint-parser.git#9c71a627da36e97da52ed2731d58509c952b67ae"
+    "typescript-eslint-parser": "git://github.com/eslint/typescript-eslint-parser.git#9c71a627da36e97da52ed2731d58509c952b67ae",
+    "unified": "6.1.5"
   },
   "devDependencies": {
     "babel-cli": "6.24.1",

diff --git a/scripts/build/build.js b/scripts/build/build.js
@@ -15,7 +15,8 @@ const parsers = [
   "typescript",
   "graphql",
   "postcss",
-  "parse5"
+  "parse5",
+  "markdown"
 ];
 
 process.env.PATH += path.delimiter + path.join(rootDir, "node_modules", ".bin");

diff --git a/src/clean-ast.js b/src/clean-ast.js
@@ -53,11 +53,17 @@ function massageAST(ast, parent) {
       "after",
       "trailingComma",
       "parent",
-      "prev"
+      "prev",
+      "position"
     ].forEach(name => {
       delete newObj[name];
     });
 
+    // for markdown codeblock
+    if (ast.type === "code") {
+      delete newObj.value;
+    }
+
     if (
       ast.type === "media-query" ||
       ast.type === "media-query-list" ||
@@ -222,14 +228,15 @@ function massageAST(ast, parent) {
       quasis.forEach(q => delete q.value);
     }
 
-    // styled-components and graphql
+    // styled-components, graphql, markdown
     if (
       ast.type === "TaggedTemplateExpression" &&
       (ast.tag.type === "MemberExpression" ||
         (ast.tag.type === "Identifier" &&
           (ast.tag.name === "gql" ||
             ast.tag.name === "graphql" ||
-            ast.tag.name === "css")) ||
+            ast.tag.name === "css" ||
+            ast.tag.name === "md")) ||
         ast.tag.type === "CallExpression")
     ) {
       newObj.quasi.quasis.forEach(quasi => delete quasi.value);

diff --git a/src/cli-constant.js b/src/cli-constant.js
@@ -201,7 +201,8 @@ const detailedOptions = normalizeDetailedOptions({
       "less",
       "scss",
       "json",
-      "graphql"
+      "graphql",
+      "markdown"
     ],
     description: "Which parser to use.",
     getter: (value, argv) => (argv["flow-parser"] ? "flow" : value)

diff --git a/src/doc-printer.js b/src/doc-printer.js
@@ -12,8 +12,8 @@ function rootIndent() {
   return {
     indent: 0,
     align: {
-      spaces: 0,
-      tabs: 0
+      spaces: "",
+      tabs: ""
     }
   };
 }
@@ -30,17 +30,17 @@ function makeAlign(ind, n) {
     return {
       indent: 0,
       align: {
-        spaces: 0,
-        tabs: 0
+        spaces: "",
+        tabs: ""
       }
     };
   }
 
   return {
     indent: ind.indent,
     align: {
-      spaces: ind.align.spaces + n,
-      tabs: ind.align.tabs + (n ? 1 : 0)
+      spaces: ind.align.spaces + (typeof n === "number" ? " ".repeat(n) : n),
+      tabs: ind.align.tabs + (n ? "\t" : "")
     }
   };
 }
@@ -399,12 +399,12 @@ function printDocToString(doc, options) {
                   }
                 }
 
-                const length = ind.indent * options.tabWidth + ind.align.spaces;
+                const indentLength = ind.indent * options.tabWidth;
                 const indentString = options.useTabs
-                  ? "\t".repeat(ind.indent + ind.align.tabs)
-                  : " ".repeat(length);
+                  ? "\t".repeat(ind.indent) + ind.align.tabs
+                  : " ".repeat(indentLength) + ind.align.spaces;
                 out.push(newLine + indentString);
-                pos = length;
+                pos = indentLength + ind.align.spaces.length;
               }
               break;
           }

diff --git a/src/multiparser.js b/src/multiparser.js
@@ -33,6 +33,59 @@ function getSubtreeParser(path, options) {
     case "flow":
     case "typescript":
       return fromBabylonFlowOrTypeScript(path, options);
+    case "markdown":
+      return fromMarkdown(path, options);
+  }
+}
+
+function fromMarkdown(path, options) {
+  const node = path.getValue();
+
+  if (node.type === "code") {
+    const parser = getParserName(node.lang);
+    if (parser) {
+      const styleUnit = options.__inJsTemplate ? "~" : "`";
+      const style = styleUnit.repeat(
+        Math.max(3, util.getMaxContinuousCount(node.value, styleUnit) + 1)
+      );
+      return {
+        options: { parser },
+        transformDoc: doc => concat([style, node.lang, hardline, doc, style]),
+        text: node.value
+      };
+    }
+  }
+
+  return null;
+
+  function getParserName(lang) {
+    switch (lang) {
+      case "js":
+      case "jsx":
+      case "javascript":
+        return "babylon";
+      case "ts":
+      case "tsx":
+      case "typescript":
+        return "typescript";
+      case "gql":
+      case "graphql":
+        return "graphql";
+      case "css":
+        return "css";
+      case "less":
+        return "less";
+      case "scss":
+        return "scss";
+      case "json":
+      case "json5":
+        return "json";
+      case "md":
+      case "markdown":
+        return "markdown";
+      default:
+        return null;
+    }
   }
 }
 
@@ -92,11 +145,62 @@ function fromBabylonFlowOrTypeScript(path) {
         };
       }
 
+      /**
+       * md`...`
+       * markdown`...`
+       */
+      if (
+        parentParent &&
+        (parentParent.type === "TaggedTemplateExpression" &&
+          parent.quasis.length === 1 &&
+          (parentParent.tag.type === "Identifier" &&
+            (parentParent.tag.name === "md" ||
+              parentParent.tag.name === "markdown")))
+      ) {
+        return {
+          options: { parser: "markdown", __inJsTemplate: true },
+          transformDoc: doc =>
+            concat([
+              indent(
+                concat([softline, stripTrailingHardline(escapeBackticks(doc))])
+              ),
+              softline
+            ]),
+          // leading whitespaces matter in markdown
+          text: dedent(parent.quasis[0].value.cooked)
+        };
+      }
+
       break;
     }
   }
 }
 
+function dedent(str) {
+  const spaces = str.match(/\n^( *)/m)[1].length;
+  return str.replace(new RegExp(`^ {${spaces}}`, "gm"), "").trim();
+}
+
+function escapeBackticks(doc) {
+  return util.mapDoc(doc, currentDoc => {
+    if (!currentDoc.parts) {
+      return currentDoc;
+    }
+
+    const parts = [];
+
+    currentDoc.parts.forEach(part => {
+      if (typeof part === "string") {
+        parts.push(part.replace(/`/g, "\\`"));
+      } else {
+        parts.push(part);
+      }
+    });
+
+    return Object.assign({}, currentDoc, { parts });
+  });
+}
+
 function fromHtmlParser2(path, options) {
   const node = path.getValue();
 

diff --git a/src/options.js b/src/options.js
@@ -45,6 +45,8 @@ function normalize(options) {
     normalized.parser = "graphql";
   } else if (/\.json$/.test(filepath)) {
     normalized.parser = "json";
+  } else if (/\.(md|markdown)$/.test(filepath)) {
+    normalized.parser = "markdown";
   }
 
   if (normalized.parser === "json") {