feat(markdown): support TOML (#3290)

src/parser-markdown.js

@@ -22,7 +22,7 @@ const util = require("./util");
 function parse(text /*, parsers, opts*/) {
   const processor = unified()
     .use(remarkParse, { footnotes: true, commonmark: true })
-    .use(remarkFrontmatter, ["yaml"])
+    .use(remarkFrontmatter, ["yaml", "toml"])
     .use(restoreUnescapedCharacter(text))
     .use(mergeContinuousTexts)
     .use(transformInlineCode)

src/printer-markdown.js

@@ -203,6 +203,8 @@ function genericPrint(path, options, print) {
     }
     case "yaml":
       return concat(["---", hardline, node.value, hardline, "---"]);
+    case "toml":
+      return concat(["+++", hardline, node.value, hardline, "+++"]);
     case "html": {
       const parentNode = path.getParentNode();
       return parentNode.type === "root" &&

tests/markdown_toml/__snapshots__/jsfmt.spec.js.snap

@@ -0,0 +1,16 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`simple.md 1`] = `
++++
+date: '2017-10-10T22:49:47.369Z'
+title: 'My Post Title'
+categories: ['foo', 'bar']
++++
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
++++
+date: '2017-10-10T22:49:47.369Z'
+title: 'My Post Title'
+categories: ['foo', 'bar']
++++
+
+`;

tests/markdown_toml/jsfmt.spec.js

@@ -0,0 +1 @@
+run_spec(__dirname, { parser: "markdown" });

tests/markdown_toml/simple.md

@@ -0,0 +1,5 @@
++++
+date: '2017-10-10T22:49:47.369Z'
+title: 'My Post Title'
+categories: ['foo', 'bar']
++++