feat(listable): Add --toposort option

Fixes #1652

commands/changed/README.md

@@ -23,6 +23,7 @@ package-2
 * [`-a`, `--all`](https://github.com/lerna/lerna/tree/master/commands/list#--all)
 * [`-l`, `--long`](https://github.com/lerna/lerna/tree/master/commands/list#--long)
 * [`-p`, `--parseable`](https://github.com/lerna/lerna/tree/master/commands/list#--parseable)
+* [`--toposort`](https://github.com/lerna/lerna/tree/master/commands/list#--toposort)
 
 Unlike `lerna ls`, however, `lerna changed` **does not** support [filter options](https://www.npmjs.com/package/@lerna/filter-options), as filtering is not supported by `lerna version` or `lerna publish`.
 

commands/list/README.md

@@ -28,6 +28,7 @@ In any case, you can always pass `--loglevel silent` to create pristine chains o
 * [`-a`, `--all`](#--all)
 * [`-l`, `--long`](#--long)
 * [`-p`, `--parseable`](#--parseable)
+* [`--toposort`](#--toposort)
 
 `lerna ls` also respects all available [Filter Flags](https://www.npmjs.com/package/@lerna/filter-options).
 
@@ -114,3 +115,18 @@ $ lerna ls -pla
 /path/to/packages/pkg-2:package-2:1.0.2
 /path/to/packages/pkg-3:package-3:1.0.3:PRIVATE
 ```
+
+### `--toposort`
+
+Sort packages in topological order (dependencies before dependents) instead of lexical by directory.
+
+```sh
+$ json dependencies <packages/pkg-1/package.json
+{
+  "pkg-2": "file:../pkg-2"
+}
+
+$ lerna ls --toposort
+package-2
+package-1
+```

utils/listable/__tests__/listable-format.test.js

@@ -4,6 +4,7 @@ const chalk = require("chalk");
 const path = require("path");
 const tempy = require("tempy");
 const Package = require("@lerna/package");
+const loggingOutput = require("@lerna-test/logging-output");
 const listable = require("..");
 
 // keep snapshots stable cross-platform
@@ -34,9 +35,18 @@ describe("listable.format()", () => {
     process.chdir(cwd);
 
     packages = [
-      new Package({ name: "pkg-1", version: "1.0.0" }, path.join(cwd, "/pkgs/pkg-1")),
-      new Package({ name: "pkg-2" }, path.join(cwd, "/pkgs/pkg-2")),
-      new Package({ name: "pkg-3", version: "3.0.0", private: true }, path.join(cwd, "/pkgs/pkg-3")),
+      new Package(
+        { name: "pkg-1", version: "1.0.0", dependencies: { "pkg-2": "file:../pkg-2" } },
+        path.join(cwd, "/pkgs/pkg-1")
+      ),
+      new Package(
+        { name: "pkg-2", devDependencies: { "pkg-3": "file:../pkg-3" } },
+        path.join(cwd, "/pkgs/pkg-2")
+      ),
+      new Package(
+        { name: "pkg-3", version: "3.0.0", dependencies: { "pkg-2": "file:../pkg-2" }, private: true },
+        path.join(cwd, "/pkgs/pkg-3")
+      ),
     ];
   });
 
@@ -174,6 +184,28 @@ pkg-3  v3.0.0 pkgs/pkg-3 (PRIVATE)
       expect(text).toMatchInlineSnapshot(`
 pkg-1  v1.0.0 pkgs/pkg-1
 pkg-2 MISSING pkgs/pkg-2
+`);
+    });
+  });
+
+  describe("toposort", () => {
+    test("output", () => {
+      const { text } = formatWithOptions({ toposort: true });
+
+      expect(text).toMatchInlineSnapshot(`
+pkg-2
+pkg-1
+`);
+    });
+
+    test("cycles", () => {
+      const { text } = formatWithOptions({ toposort: true, all: true });
+
+      expect(loggingOutput("warn")).toContainEqual(expect.stringContaining("pkg-2 -> pkg-3 -> pkg-2"));
+      expect(text).toMatchInlineSnapshot(`
+pkg-2
+pkg-3 (PRIVATE)
+pkg-1
 `);
     });
   });

utils/listable/__tests__/listable-options.test.js

@@ -33,4 +33,8 @@ describe("listable.options()", () => {
   it("provides --parseable alias -p", () => {
     expect(parsed("-p")).toHaveProperty("parseable", true);
   });
+
+  it("provides --toposort", () => {
+    expect(parsed("--toposort")).toHaveProperty("toposort", true);
+  });
 });

utils/listable/lib/listable-format.js

@@ -3,6 +3,7 @@
 const chalk = require("chalk");
 const columnify = require("columnify");
 const path = require("path");
+const batchPackages = require("@lerna/batch-packages");
 
 module.exports = listableFormat;
 
@@ -32,11 +33,24 @@ function parseViewOptions(options) {
     showLong: alias === "la" || alias === "ll" || options.long,
     showJSON: options.json,
     showParseable: options.parseable,
+    isTopological: options.toposort,
   };
 }
 
+function flatBatched(pkgList) {
+  const batches = batchPackages(pkgList);
+
+  return batches.reduce((acc, batch) => acc.concat(batch), []);
+}
+
 function filterResultList(pkgList, viewOptions) {
-  return viewOptions.showAll ? pkgList.slice() : pkgList.filter(pkg => !pkg.private);
+  let result = viewOptions.showAll ? pkgList.slice() : pkgList.filter(pkg => !pkg.private);
+
+  if (viewOptions.isTopological) {
+    result = flatBatched(result);
+  }
+
+  return result;
 }
 
 function formatJSON(resultList) {

utils/listable/lib/listable-options.js

@@ -27,5 +27,10 @@ function listableOptions(yargs) {
       type: "boolean",
       alias: "parseable",
     },
+    toposort: {
+      group: "Command Options:",
+      describe: "Sort packages in topological order instead of lexical by directory",
+      type: "boolean",
+    },
   });
 }

utils/listable/package.json

@@ -28,6 +28,7 @@
     "test": "echo \"Error: run tests from root\" && exit 1"
   },
   "dependencies": {
+    "@lerna/batch-packages": "file:../batch-packages",
     "chalk": "^2.3.1",
     "columnify": "^1.5.4"
   }