API: add resolveConfig option to getFileInfo() (#6666)

* Add useConfig option to getFileInfo()

* useConfig -> resolveConfig

CHANGELOG.unreleased.md

@@ -44,6 +44,10 @@ const link = <a href="example.com">http://example.com</a>;
 
 -->
 
+#### API: add resolveConfig option to getFileInfo() ([#6666] by [@kaicataldo])
+
+Add a `resolveConfig: boolean` option to `prettier.getFileInfo()` that, when set to `true`, will resolve the configuration for the given file path. This allows consumers to take any overridden parsers into account.
+
 #### JavaScript: add support for PartialApplication ([#6397] by [@JounQin])
 
 Previous versions would not be able to format this syntax, this has been fixed in this version.

docs/api.md

@@ -100,6 +100,8 @@ Setting `options.ignorePath` (`string`) and `options.withNodeModules` (`boolean`
 
 Providing [plugin](plugins.md) paths in `options.plugins` (`string[]`) helps extract `inferredParser` for files that are not supported by Prettier core.
 
+When setting `options.resolveConfig` (`boolean`, default `false`), Prettier will resolve the configuration for the given `filePath`. This is useful, for example, when the `inferredParser` might be overridden for a subset of files.
+
 Use `prettier.getFileInfo.sync(filePath [, options])` if you'd like to use sync version.
 
 ## `prettier.getSupportInfo([version])`

src/common/get-file-info.js

@@ -2,6 +2,7 @@
 
 const createIgnorer = require("./create-ignorer");
 const options = require("../main/options");
+const config = require("../config/resolve-config");
 const path = require("path");
 
 /**
@@ -28,11 +29,13 @@ function getFileInfo(filePath, opts) {
   }
 
   return createIgnorer(opts.ignorePath, opts.withNodeModules).then(ignorer =>
-    _getFileInfo(
+    _getFileInfo({
       ignorer,
-      normalizeFilePath(filePath, opts.ignorePath),
-      opts.plugins
-    )
+      filePath: normalizeFilePath(filePath, opts.ignorePath),
+      plugins: opts.plugins,
+      resolveConfig: opts.resolveConfig,
+      sync: false
+    })
   );
 }
 
@@ -49,21 +52,45 @@ getFileInfo.sync = function(filePath, opts) {
   }
 
   const ignorer = createIgnorer.sync(opts.ignorePath, opts.withNodeModules);
-  return _getFileInfo(
+  return _getFileInfo({
     ignorer,
-    normalizeFilePath(filePath, opts.ignorePath),
-    opts.plugins
-  );
+    filePath: normalizeFilePath(filePath, opts.ignorePath),
+    plugins: opts.plugins,
+    resolveConfig: opts.resolveConfig,
+    sync: true
+  });
 };
 
-function _getFileInfo(ignorer, filePath, plugins) {
-  const ignored = ignorer.ignores(filePath);
-  const inferredParser = options.inferParser(filePath, plugins) || null;
-
-  return {
-    ignored,
-    inferredParser
+function _getFileInfo({
+  ignorer,
+  filePath,
+  plugins,
+  resolveConfig = false,
+  sync = false
+}) {
+  const fileInfo = {
+    ignored: ignorer.ignores(filePath),
+    inferredParser: options.inferParser(filePath, plugins) || null
   };
+
+  if (!fileInfo.inferredParser && resolveConfig) {
+    if (!sync) {
+      return config.resolveConfig(filePath).then(resolvedConfig => {
+        if (resolvedConfig && resolvedConfig.parser) {
+          fileInfo.inferredParser = resolvedConfig.parser;
+        }
+
+        return fileInfo;
+      });
+    }
+
+    const resolvedConfig = config.resolveConfig.sync(filePath);
+    if (resolvedConfig && resolvedConfig.parser) {
+      fileInfo.inferredParser = resolvedConfig.parser;
+    }
+  }
+
+  return fileInfo;
 }
 
 function normalizeFilePath(filePath, ignorePath) {

tests_integration/__tests__/file-info.js

@@ -131,6 +131,142 @@ test("API getFileInfo.sync with filepath only", () => {
   });
 });
 
+test("API getFileInfo with resolveConfig", () => {
+  const file1 = path.resolve(
+    path.join(__dirname, "../cli/with-resolve-config/file.foo")
+  );
+  const file2 = path.resolve(
+    path.join(__dirname, "../cli/with-resolve-config/file.bar")
+  );
+
+  expect(prettier.getFileInfo(file1)).resolves.toMatchObject({
+    ignored: false,
+    inferredParser: null
+  });
+  expect(prettier.getFileInfo(file2)).resolves.toMatchObject({
+    ignored: false,
+    inferredParser: null
+  });
+  expect(
+    prettier.getFileInfo(file1, {
+      resolveConfig: true
+    })
+  ).resolves.toMatchObject({
+    ignored: false,
+    inferredParser: "json"
+  });
+  expect(
+    prettier.getFileInfo(file2, {
+      resolveConfig: true
+    })
+  ).resolves.toMatchObject({
+    ignored: false,
+    inferredParser: "babel"
+  });
+});
+
+test("API getFileInfo with resolveConfig when no config is present", () => {
+  const file1 = path.resolve(
+    path.join(__dirname, "../cli/with-resolve-config-no-config/file.foo")
+  );
+  const file2 = path.resolve(
+    path.join(__dirname, "../cli/with-resolve-config-no-config/file.bar")
+  );
+
+  expect(prettier.getFileInfo(file1)).resolves.toMatchObject({
+    ignored: false,
+    inferredParser: null
+  });
+  expect(prettier.getFileInfo(file2)).resolves.toMatchObject({
+    ignored: false,
+    inferredParser: null
+  });
+  expect(
+    prettier.getFileInfo(file1, {
+      resolveConfig: true
+    })
+  ).resolves.toMatchObject({
+    ignored: false,
+    inferredParser: null
+  });
+  expect(
+    prettier.getFileInfo(file2, {
+      resolveConfig: true
+    })
+  ).resolves.toMatchObject({
+    ignored: false,
+    inferredParser: null
+  });
+});
+
+test("API getFileInfo.sync with resolveConfig", () => {
+  const file1 = path.resolve(
+    path.join(__dirname, "../cli/with-resolve-config/file.foo")
+  );
+  const file2 = path.resolve(
+    path.join(__dirname, "../cli/with-resolve-config/file.bar")
+  );
+
+  expect(prettier.getFileInfo.sync(file1)).toMatchObject({
+    ignored: false,
+    inferredParser: null
+  });
+  expect(prettier.getFileInfo.sync(file2)).toMatchObject({
+    ignored: false,
+    inferredParser: null
+  });
+  expect(
+    prettier.getFileInfo.sync(file1, {
+      resolveConfig: true
+    })
+  ).toMatchObject({
+    ignored: false,
+    inferredParser: "json"
+  });
+  expect(
+    prettier.getFileInfo.sync(file2, {
+      resolveConfig: true
+    })
+  ).toMatchObject({
+    ignored: false,
+    inferredParser: "babel"
+  });
+});
+
+test("API getFileInfo.sync with resolveConfig when no config is present", () => {
+  const file1 = path.resolve(
+    path.join(__dirname, "../cli/with-resolve-config-no-config/file.foo")
+  );
+  const file2 = path.resolve(
+    path.join(__dirname, "../cli/with-resolve-config-no-config/file.bar")
+  );
+
+  expect(prettier.getFileInfo.sync(file1)).toMatchObject({
+    ignored: false,
+    inferredParser: null
+  });
+  expect(prettier.getFileInfo.sync(file2)).toMatchObject({
+    ignored: false,
+    inferredParser: null
+  });
+  expect(
+    prettier.getFileInfo.sync(file1, {
+      resolveConfig: true
+    })
+  ).toMatchObject({
+    ignored: false,
+    inferredParser: null
+  });
+  expect(
+    prettier.getFileInfo.sync(file2, {
+      resolveConfig: true
+    })
+  ).toMatchObject({
+    ignored: false,
+    inferredParser: null
+  });
+});
+
 test("API getFileInfo with ignorePath", () => {
   const file = path.resolve(
     path.join(__dirname, "../cli/ignore-path/regular-module.js")

tests_integration/cli/with-resolve-config-no-config/file.bar

@@ -0,0 +1 @@
+const foo = "bar";

tests_integration/cli/with-resolve-config-no-config/file.foo

@@ -0,0 +1 @@
+{}

tests_integration/cli/with-resolve-config/.prettierrc

@@ -0,0 +1,12 @@
+{
+  "overrides": [
+    {
+      "files": "*.foo",
+      "options": { "parser": "json" }
+    },
+    {
+      "files": "*.bar",
+      "options": { "parser": "babel" }
+    }
+  ]
+}

tests_integration/cli/with-resolve-config/file.bar

@@ -0,0 +1 @@
+const foo = "bar";

tests_integration/cli/with-resolve-config/file.foo

@@ -0,0 +1 @@
+{}