Prepare async path resolving

Author: TrySound

index.js

@@ -5,20 +5,19 @@ var fs = require("fs")
 var path = require("path")
 
 var assign = require("object-assign")
-var resolve = require("resolve")
 var postcss = require("postcss")
 var helpers = require("postcss-message-helpers")
 var glob = require("glob")
 var parseImports = require("./lib/parse-imports")
 var resolveMedia = require("./lib/resolve-media")
+var resolveId = require("./lib/resolve-id")
 
 /**
  * Constants
  */
 var moduleDirectories = [
   "web_modules",
   "node_modules",
-  "bower_components",
 ]
 
 /**
@@ -256,42 +255,48 @@ function readAtImport(
     return Promise.resolve()
   }
 
+  var dir = atRule.source && atRule.source.input && atRule.source.input.file
+    ? path.dirname(path.resolve(options.root, atRule.source.input.file))
+    : options.root
+
   addInputToPath(options)
-  var resolvedFilename = resolveFilename(
-    parsedAtImport.uri,
-    options.root,
-    options.path,
-    atRule.source,
-    options.resolve
-  )
 
-  if (options.skipDuplicates) {
-    // skip files already imported at the same scope
-    if (
-      state.importedFiles[resolvedFilename] &&
-      state.importedFiles[resolvedFilename][media]
-    ) {
-      atRule.remove()
-      return Promise.resolve()
+  return Promise.resolve().then(function() {
+    if (options.resolve) {
+      return options.resolve(parsedAtImport.uri, dir, options)
     }
+    return resolveId(parsedAtImport.uri, dir, options.path)
+  }).then(function(resolvedFilename) {
+    if (options.skipDuplicates) {
+      // skip files already imported at the same scope
+      if (
+        state.importedFiles[resolvedFilename] &&
+        state.importedFiles[resolvedFilename][media]
+      ) {
+        atRule.remove()
+        return Promise.resolve()
+      }
 
-    // save imported files to skip them next time
-    if (!state.importedFiles[resolvedFilename]) {
-      state.importedFiles[resolvedFilename] = {}
+      // save imported files to skip them next time
+      if (!state.importedFiles[resolvedFilename]) {
+        state.importedFiles[resolvedFilename] = {}
+      }
+      state.importedFiles[resolvedFilename][media] = true
     }
-    state.importedFiles[resolvedFilename][media] = true
-  }
 
-  return readImportedContent(
-    result,
-    atRule,
-    parsedAtImport,
-    assign({}, options),
-    resolvedFilename,
-    state,
-    media,
-    processor
-  )
+    return readImportedContent(
+      result,
+      atRule,
+      parsedAtImport,
+      assign({}, options),
+      resolvedFilename,
+      state,
+      media,
+      processor
+    )
+  }).catch(function(err) {
+    result.warn(err.message, { node: atRule })
+  })
 }
 
 /**
@@ -414,63 +419,6 @@ function insertRules(atRule, parsedAtImport, newStyles) {
   atRule.replaceWith(newNodes)
 }
 
-/**
- * Check if a file exists
- *
- * @param {String} name
- */
-function resolveFilename(name, root, paths, source, resolver) {
-  var dir = source && source.input && source.input.file
-    ? path.dirname(path.resolve(root, source.input.file))
-    : root
-
-  try {
-    var resolveOpts = {
-      basedir: dir,
-      moduleDirectory: moduleDirectories.concat(paths),
-      paths: paths,
-      extensions: [ ".css" ],
-      packageFilter: function processPackage(pkg) {
-        pkg.main = pkg.style || "index.css"
-        return pkg
-      },
-    }
-    var file
-    resolver = resolver || resolve.sync
-    try {
-      file = resolver(name, resolveOpts)
-    }
-    catch (e) {
-      // fix to try relative files on windows with "./"
-      // if it's look like it doesn't start with a relative path already
-      // if (name.match(/^\.\.?/)) {throw e}
-      try {
-        file = resolver("./" + name, resolveOpts)
-      }
-      catch (err) {
-        // LAST HOPE
-        if (!paths.some(function(dir2) {
-          file = path.join(dir2, name)
-          return fs.existsSync(file)
-        })) {
-          throw err
-        }
-      }
-    }
-
-    return path.normalize(file)
-  }
-  catch (e) {
-    throw new Error(
-      "Failed to find '" + name + "' from " + root +
-      "\n    in [ " +
-      "\n        " + paths.join(",\n        ") +
-      "\n    ]",
-      source
-    )
-  }
-}
-
 /**
  * Read the contents of a file
  *

lib/resolve-id.js

@@ -0,0 +1,54 @@
+var fs = require("fs")
+var path = require("path")
+var resolve = require("resolve")
+
+var moduleDirectories = [
+  "web_modules",
+  "node_modules",
+]
+
+module.exports = function(id, base, paths) {
+  try {
+    var resolveOpts = {
+      basedir: base,
+      moduleDirectory: moduleDirectories,
+      paths: paths,
+      extensions: [ ".css" ],
+      packageFilter: function processPackage(pkg) {
+        pkg.main = pkg.style || "index.css"
+        return pkg
+      },
+    }
+    var file
+    try {
+      file = resolve.sync(id, resolveOpts)
+    }
+    catch (e) {
+      // fix to try relative files on windows with "./"
+      // if it's look like it doesn't start with a relative path already
+      // if (id.match(/^\.\.?/)) {throw e}
+      try {
+        file = resolve.sync("./" + id, resolveOpts)
+      }
+      catch (err) {
+        // LAST HOPE
+        if (!paths.some(function(dir) {
+          file = path.join(dir, id)
+          return fs.existsSync(file)
+        })) {
+          throw err
+        }
+      }
+    }
+
+    return path.normalize(file)
+  }
+  catch (e) {
+    throw new Error([
+      "Failed to find '" + id + "'",
+      "in [ ",
+      "    " + paths.join(",\n        "),
+      "]",
+    ].join("\n    "))
+  }
+}

test/fixtures/ignore.expected.css

@@ -1,6 +1,3 @@
-@import "http://css" (min-width: 25em);
-
-@import "http://css-screen" (min-width: 25em) and screen;
 
 @import "http://css";
 
@@ -28,6 +25,10 @@
 
 @import url(//css);
 
+@import "http://css" (min-width: 25em);
+
+@import "http://css-screen" (min-width: 25em) and screen;
+
 @media (min-width: 25em){
 ignore{}
 }

test/import.js

@@ -1,4 +1,5 @@
 import test from "ava"
+import path from "path"
 import { readFileSync } from "fs"
 import postcss from "postcss"
 import atImport from ".."
@@ -85,13 +86,11 @@ test("should output readable trace", t => {
   return postcss()
     .use(atImport())
     .process(readFileSync(file), { from: file })
-    .catch(error => {
-      t.throws(
-        () => {
-          throw error
-        },
+    .then(result => {
+      t.is(
+        result.warnings()[0].text,
         /* eslint-disable max-len */
-        /import-missing.css:2:5: Failed to find 'missing-file.css' from .*\n\s+in \[/gm
+        "Failed to find 'missing-file.css'\n    in [ \n        " + path.resolve("fixtures/imports") + "\n    ]"
         /* eslint-enabme max-len */
       )
     })
@@ -155,14 +154,16 @@ test("should work with no styles without throwing an error", t => {
 
 test("should be able to consume modules in the custom-resolve way", t => {
   const resolve = require("resolve")
-  const sassResolve = (file, opts) => {
-    opts = opts || {}
-    opts.extensions = [ ".scss", ".css" ]
-    opts.packageFilter = pkg => {
-      pkg.main = pkg.sass || pkg.style || "index"
-      return pkg
-    }
-    return resolve.sync(file, opts)
+  const sassResolve = (id, base, opts) => {
+    return resolve.sync(id, {
+      basedir: base,
+      extensions: [ ".scss", ".css" ],
+      paths: opts.path,
+      packageFilter: pkg => {
+        pkg.main = pkg.sass || pkg.style || "index"
+        return pkg
+      },
+    })
   }
   return compareFixtures(t, "custom-resolve-modules", {
     root: ".",