Updated walk() to print out more information on exception

nikhilgaba · ai · commit b2530e0f7a10 · 2018-07-16T10:52:18.000-07:00
diff --git a/lib/container.es6 b/lib/container.es6
@@ -105,7 +105,18 @@ class Container extends Node {
    */
   walk (callback) {
     return this.each((child, i) => {
-      let result = callback(child, i)
+      let result
+      try {
+        result = callback(child, i)
+      } catch (e) {
+        e.postcssNode = child
+        if (e.stack && child.source && /\n\s{4}at /.test(e.stack)) {
+          const s = child.source
+          e.stack = e.stack.replace(/\n\s{4}at /,
+            `$&${ s.input.from }:${ s.start.line }:${ s.start.column }$&`)
+        }
+        throw e
+      }
       if (result !== false && child.walk) {
         result = child.walk(callback)
       }
diff --git a/test/container.test.js b/test/container.test.js
@@ -182,6 +182,24 @@ it('walk() breaks iteration', () => {
   expect(indexes).toEqual([0])
 })
 
+it('walk() adds CSS position to error stack', () => {
+  const error = new Error('T')
+  error.stack = 'Error: T\n    at b (b.js:2:4)\n    at a (a.js:2:1)'
+  const root = parse(example, { from: '/c.css' })
+  let catched
+  try {
+    root.walk(() => {
+      throw error
+    })
+  } catch (e) {
+    catched = e
+  }
+  expect(catched).toBe(error)
+  expect(catched.postcssNode.toString()).toEqual('a { a: 1; b: 2 }')
+  expect(catched.stack).toEqual(
+    'Error: T\n    at /c.css:1:1\n    at b (b.js:2:4)\n    at a (a.js:2:1)')
+})
+
 it('walkDecls() iterates', () => {
   const props = []
   const indexes = []
