fix(markdown): stably print lists in front of whitespace-only trailing newline (#5024)

src/language-markdown/parser-markdown.js

@@ -379,7 +379,8 @@ const baseParser = {
   astFormat: "mdast",
   hasPragma: pragma.hasPragma,
   locStart: node => node.position.start.offset,
-  locEnd: node => node.position.end.offset
+  locEnd: node => node.position.end.offset,
+  preprocess: text => text.replace(/\n\s+$/, "\n") // workaround for https://github.com/remarkjs/remark/issues/350
 };
 
 const markdownParser = Object.assign({}, baseParser, {

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

@@ -98,6 +98,82 @@ markdown\`
 
 `;
 
+exports[`issue-5021.js - babylon-verify 1`] = `
+if (true) {
+  md\`
+text1
+- 123
+  - 456
+
+text2
+- 123
+  - 456
+
+text3
+- 123
+  - 456
+\`;
+}
+
+if (true) {
+  md\`
+text1
+
+- 123
+  - 456
+
+text2
+
+- 123
+  - 456
+
+text3
+
+- 123
+  - 456
+  \`;
+}
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+if (true) {
+  md\`
+text1
+
+- 123
+  - 456
+
+text2
+
+- 123
+  - 456
+
+text3
+
+- 123
+  - 456
+  \`;
+}
+
+if (true) {
+  md\`
+text1
+
+- 123
+  - 456
+
+text2
+
+- 123
+  - 456
+
+text3
+
+- 123
+  - 456
+  \`;
+}
+
+`;
+
 exports[`markdown.js - babylon-verify 1`] = `
 export default function ReadMe() {
     return md\`

tests/multiparser_js_markdown/issue-5021.js

@@ -0,0 +1,34 @@
+if (true) {
+  md`
+text1
+- 123
+  - 456
+
+text2
+- 123
+  - 456
+
+text3
+- 123
+  - 456
+`;
+}
+
+if (true) {
+  md`
+text1
+
+- 123
+  - 456
+
+text2
+
+- 123
+  - 456
+
+text3
+
+- 123
+  - 456
+  `;
+}