Merge pull request #5 from alternate-file/features/multi-dirname

Features/multi dirname

Author: will-wow

.projections.json

@@ -1,3 +1,3 @@
 {
-  "src/*.ts": { "alternate": ["src/test/{}.test.ts", "src/{}.test.ts"] }
+  "src/*.ts": { "alternate": ["src/{}.test.ts", "src/test/{}.test.ts"] }
 }

.vscodeignore

@@ -1,12 +1,15 @@
-.vscode/**
+.build.yml
+.gitignore
+.prettierignore
+.projections.json
 .vscode-test/**
-out/test/**
+.vscode/**
+assets/screencasts
 out/**/*.map
+out/test/**
 src/**
-.gitignore
+test-project
 tsconfig.json
-vsc-extension-quickstart.md
 tslint.json
-yarn.lock
-test-project
-assets/screencasts
+vsc-extension-quickstart.md
+yarn.lock

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 - Support finding .projections.json in places other than the workspace.
+- Support multiple dirname parts
 
 ### Changed
 

README.md

@@ -27,6 +27,14 @@ Each line should have the pattern for an implementation file as the key, and an
 
 If your test paths have an extra directly in the middle of them, like with `app/some/path/__test__/file.test.js` with Jest, you can use `{dirname}` for the directory path and `{basename}` for the filename. You can do the same thing on the implementation side with the standard glob syntax: `**` to represent the directory path, and `*` to represent the filename, like `app/**/something/*.js`.
 
+If your paths have more than two variable parts, that can work too! You can use multiple sets of `**`/`{dirname}` pairs, which allows you to do something like:
+
+```json
+"apps/**/lib/**/*.ex": {
+  "alternate": "apps/{dirname}/test/{dirname}/{basename}_test.exs"
+}
+```
+
 ### Multiple alternates
 
 If your project is inconsistent about where specs go (it happens to the best of us), you can also pass an array to `alternate`. The extension will look for a file matching the first alternate, then the second, and so on. When you create an alternate file, it will always follow the first pattern.
@@ -119,4 +127,4 @@ Click the Debug button in the sidebar and run `Extension`
 - Support templates for auto-populating new files.
 - Automatically create default .projection.json files
 - Support all the transformations from Projectionist, not just `dirname` and `basename`.
-- Support the "type" attribute in `.projections.json`, and allow for lookup by filetype, like for "controller/view/template".
+- Support the "type" attribute in `.projections.json`, and allow for lookup by filetype, like for "`controller`/`view`/`template`".

package.json

@@ -25,6 +25,9 @@
     "alt": "./bin/cli.js"
   },
   "icon": "assets/icon.png",
+  "galleryBanner": {
+    "color": "#3771C8"
+  },
   "activationEvents": [
     "onCommand:alternate.alternateFile",
     "onCommand:alternate.alternateFileInSplit",

sample-projections/projections.elixir-umbrella.json

@@ -0,0 +1,5 @@
+{
+  "apps/**/lib/**/*.ex": {
+    "alternate": "apps/{dirname}/test/{dirname}/{basename}_test.exs"
+  }
+}

src/engine/AlternatePattern.test.ts

@@ -10,6 +10,10 @@ describe("AlternatePattern", () => {
     {
       main: "app/{dirname}/{basename}.rb",
       alternate: "test/{dirname}/{basename}_spec.rb"
+    },
+    {
+      main: "apps/{dirname}/lib/{dirname}/{basename}.ex",
+      alternate: "apps/{dirname}/test/{dirname}/{basename}_test.exs"
     }
   ];
 
@@ -20,34 +24,44 @@ describe("AlternatePattern", () => {
     it("finds an implementation from a test", () => {
       expect(
         AlternatePattern.alternatePath(
-          "src/components/__test__/Foo.test.ts",
+          "/project/src/components/__test__/Foo.test.ts",
           projectionsPath
         )(patterns[0])
       ).toBe("/project/src/components/Foo.ts");
     });
 
     it("finds alternate for short path", () => {
       expect(
-        AlternatePattern.alternatePath("app/foo.rb", projectionsPath)(
+        AlternatePattern.alternatePath("/project/app/foo.rb", projectionsPath)(
           patterns[1]
         )
       ).toBe("/project/test/foo_spec.rb");
     });
 
     it("finds ts specs", () => {
       expect(
-        AlternatePattern.alternatePath("./src/foo/bar.ts", projectionsPath)(
-          patterns[0]
-        )
+        AlternatePattern.alternatePath(
+          "/project/src/foo/bar.ts",
+          projectionsPath
+        )(patterns[0])
       ).toBe("/project/src/foo/__test__/bar.test.ts");
     });
 
     it("returns null for non-matches", () => {
       expect(
-        AlternatePattern.alternatePath("src/foo.rb", projectionsPath)(
+        AlternatePattern.alternatePath("/project/src/foo.rb", projectionsPath)(
           patterns[0]
         )
       ).toBe(null);
     });
+
+    it("finds a match with multiple dirnames", () => {
+      const path = AlternatePattern.alternatePath(
+        "/project/apps/my_app/lib/accounts/user.ex",
+        projectionsPath
+      )(patterns[2]);
+
+      expect(path).toBe("/project/apps/my_app/test/accounts/user_test.exs");
+    });
   });
 });

src/engine/AlternatePattern.ts

@@ -1,4 +1,6 @@
 import * as path from "path";
+import * as utils from "./utils";
+import * as Result from "../result/Result";
 
 /**
  * A computer-friendly representation of paths for switching between alternate files.
@@ -8,23 +10,28 @@ export interface t {
   alternate: string;
 }
 
-const slash = "/";
-const backslash = "\\\\";
-const anyBackslashRegex = new RegExp(backslash, "g");
+const slash = "[/\\]";
+const notSlash = "[^/\\]";
+const escapedSlash = "[/\\\\]";
 
-const dirnameRegex = new RegExp(
-  `{dirname}(?:${slash}|${backslash}${backslash})`,
-  "g"
-);
+const anyBackslashRegex = /\\/g;
+const escapedBackslash = "\\\\";
+
+const transformationPattern = "{([^{}]+)}";
+
+const dirnameRegex = new RegExp(`{dirname}${escapedSlash}`, "g");
 const basenameRegex = /{basename}/g;
 
-const dirnamePattern = `(?:(.+)[${slash}${backslash}])?`;
-const basenamePattern = `([^${slash}${backslash}]+)`;
+const dirnamePattern = `(?:(.+)${slash})?`;
+const basenamePattern = `(${notSlash}+)`;
 
 /**
- * Use an AlternatePath to find a possible alternate path for a file.
- * @param path
- * @param projectionsPath
+ * Given a filePath and an AlternatePath, calculate if the filePath matches
+ * a pattern, and if it does, calculate what the matching alternate file path
+ * would be.
+ * @param path - the absolute path to the file
+ * @param projectionsPath - the absolute path to the projections file
+ * @param alternatePath - the AlternatePath object to match against.
  */
 export const alternatePath = (path: string, projectionsPath: string) => ({
   main,
@@ -45,31 +52,101 @@ const alternatePathForSide = (
     alternatePattern
   );
 
-  const regex = patternToRegex(absolutePattern);
+  const matchResult = matchPatternToPath(absolutePattern, filePath);
+  if (Result.isError(matchResult)) return null;
+
+  const pathMatches = matchResult.ok;
+  const transformations = patternToTransformations(absolutePattern);
+
+  return fillPattern(transformations, pathMatches, absoluteAlternatePattern);
+};
+
+/**
+ * Take the available transformation names and match values, and use them to fill up the alternate pattern.
+ * @param transformations
+ * @param matches
+ * @param alternatePattern
+ * @returns A complete file path.
+ */
+const fillPattern = (
+  transformations: string[],
+  matches: string[],
+  alternatePattern: string
+): string => {
+  const filledPath = utils
+    .zip(transformations, matches)
+    .reduce(
+      (alternatePattern: string, [transformation, match]: [string, string]) =>
+        alternatePattern.replace(`{${transformation}}`, match || ""),
+      alternatePattern
+    );
+
+  return path.normalize(filledPath);
+};
+
+/**
+ * Extract a list of transformations from a pattern, to be zipped with their matches.
+ * @param pathPattern
+ * @returns list of transformation names
+ */
+const patternToTransformations = (pathPattern: string) => {
+  const regex = new RegExp(transformationPattern, "g");
+
+  const transformations: string[] = [];
+  let matches: RegExpExecArray | null;
+
+  while ((matches = regex.exec(pathPattern)) !== null) {
+    transformations.push(matches[1]);
+  }
+
+  return transformations;
+};
+
+/**
+ * Take a path pattern string, and use it to try to pull out matches from the file path.
+ * @param pathPattern - String to be converted to regex
+ * @param filePath - Current file
+ * @returns Ok(matches) | Error(null) if no matches
+ */
+const matchPatternToPath = (
+  pathPattern: string,
+  filePath: string
+): Result.Result<string[], null> => {
+  const regex = patternToRegex(pathPattern);
   const matches = filePath.match(regex);
 
-  if (!matches || !matches[2]) return null;
+  if (!matches || !matches[2]) return Result.error(null);
 
-  const dirname = matches[1];
-  const basename = matches[2];
+  const pathMatches = matches.slice(1);
 
-  return path.normalize(
-    absoluteAlternatePattern
-      .replace(dirnameRegex, dirname ? `${dirname}/` : "")
-      .replace(basenameRegex, basename)
-  );
+  return Result.ok(pathMatches);
 };
 
+/**
+ * Take a projections pattern, and convert it to a regex that will extract the variable parts.
+ */
 const patternToRegex = (pathPattern: string): RegExp => {
   const regexPattern = pathPattern
     .replace(dirnameRegex, dirnamePattern)
     .replace(basenameRegex, basenamePattern);
-  return new RegExp(regexPattern);
+
+  const escapedPattern = escapeBackslashes(regexPattern);
+
+  return new RegExp(escapedPattern);
 };
 
+/**
+ * Append a pattern to the absolute path of the projections file
+ * @param projectionsPath - absolute path to the projections file
+ * @param filePattern -
+ */
 const combinePaths = (projectionsPath: string, filePattern: string): string => {
   const projectionsDir = path.dirname(projectionsPath);
-  const fullPath = path.resolve(projectionsDir, filePattern);
-
-  return fullPath.replace(anyBackslashRegex, backslash);
+  return path.resolve(projectionsDir, filePattern);
 };
+
+/**
+ * Escape backslashes before converting a string to a regex.
+ */
+const escapeBackslashes = (pattern: string): string =>
+  pattern.replace(anyBackslashRegex, escapedBackslash);

src/engine/File.ts

@@ -81,11 +81,15 @@ export const readFile = (path: string): Result.P<string, any> =>
  * Wrap a JSON parse in a Result.
  * @returns Ok(body)
  */
-export const parseJson = <T>(data: string): Result.Result<T, any> => {
+export const parseJson = <T>(
+  data: string,
+  fileName?: string
+): Result.Result<T, any> => {
   try {
     return Result.ok(JSON.parse(data));
   } catch (e) {
-    return Result.error(e);
+    const message = `Couldn't parse ${fileName || "file"}: ${e.message}`;
+    return Result.error(message);
   }
 };
 

src/engine/Projections.ts

@@ -121,7 +121,7 @@ export const readProjections = async (
     projectionsPath,
     File.readFile,
     Result.mapOk((data: string): string => (data === "" ? "{}" : data)),
-    Result.chainOk((x: string) => File.parseJson<t>(x)),
+    Result.chainOk((x: string) => File.parseJson<t>(x, projectionsPath)),
     Result.mapError((error: string) => ({
       startingFile: projectionsPath,
       message: error
@@ -184,7 +184,7 @@ const mainPathToAlternate = (path: string): string => {
 
   const taggedPath = /\*\*/.test(path) ? path : path.replace("*", "**/*");
 
-  return taggedPath.replace("**", "{dirname}").replace("*", "{basename}");
+  return taggedPath.replace(/\*\*/g, "{dirname}").replace("*", "{basename}");
 };
 
 const alternatePathToAlternate = (path: string): string => {