fix: pnpm recursive list/why with parseable render produce needless newlines (#3101)

* fix: pnpm why --parseable filter empty string

* docs: ✏️ run changeset

* test: add test for list monorepo with parseable

.changeset/eleven-panthers-agree.md

@@ -0,0 +1,6 @@
+---
+"@pnpm/list": patch
+"@pnpm/plugin-commands-listing": patch
+---
+
+Remove redundant empty lines when run `pnpm why --parseable`

fixtures/workspace-with-different-deps/package.json

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

fixtures/workspace-with-different-deps/packages/bar/package.json

@@ -0,0 +1,7 @@
+{
+  "name": "bar",
+  "version": "0.0.0",
+  "dependencies": {
+    "is-positive": "3.1.0"
+  }
+}

fixtures/workspace-with-different-deps/packages/foo/package.json

@@ -0,0 +1,6 @@
+{
+  "name": "foo",
+  "version": "0.0.0",
+  "dependencies": {
+  }
+}

fixtures/workspace-with-different-deps/pnpm-lock.yaml

@@ -0,0 +1,18 @@
+importers:
+  .:
+    specifiers: {}
+  packages/bar:
+    dependencies:
+      is-positive: 3.1.0
+    specifiers:
+      is-positive: 3.1.0
+  packages/foo:
+    specifiers: {}
+lockfileVersion: 5.2
+packages:
+  /is-positive/3.1.0:
+    dev: false
+    engines:
+      node: '>=0.10.0'
+    resolution:
+      integrity: sha1-hX21hKG6XRyymAUn/DtsQ103sP0=

fixtures/workspace-with-different-deps/pnpm-workspace.yaml

@@ -0,0 +1,2 @@
+packages:
+  - 'packages/**'

packages/list/src/renderParseable.ts

@@ -13,7 +13,7 @@ export default async function (
     search: boolean
   }
 ) {
-  return pkgs.map((pkg) => renderParseableForPackage(pkg, opts)).join('\n')
+  return pkgs.map((pkg) => renderParseableForPackage(pkg, opts)).filter(p => p.length !== 0).join('\n')
 }
 
 function renderParseableForPackage (

packages/list/test/index.ts

@@ -26,6 +26,7 @@ const fixtureWithNoPkgNameAndNoVersion = path.join(fixtures, 'fixture-with-no-pk
 const fixtureWithNoPkgVersion = path.join(fixtures, 'fixture-with-no-pkg-version')
 const fixtureWithExternalLockfile = path.join(fixtures, 'fixture-with-external-shrinkwrap', 'pkg')
 const workspaceWith2Pkgs = path.join(fixtures, 'workspace-with-2-pkgs')
+const workspaceWithDifferentDeps = path.join(fixtures, 'workspace-with-different-deps')
 const emptyFixture = path.join(fixtures, 'empty')
 const fixtureWithAliasedDep = path.join(fixtures, 'with-aliased-dep')
 
@@ -367,6 +368,23 @@ ${path.join(fixture, 'node_modules/.pnpm/is-positive@3.1.0')}`
   )
 })
 
+test('parseable list with depth 1 without unnecessary empty newlines', async () => {
+  expect(await listForPackages(
+    ['is-positive'],
+    [
+      path.join(workspaceWithDifferentDeps, 'packages/bar'),
+      path.join(workspaceWithDifferentDeps, 'packages/foo'),
+    ], {
+      alwaysPrintRootPackage: false,
+      lockfileDir: workspaceWithDifferentDeps,
+      depth: 1,
+      reportAs: 'parseable',
+    }
+  )).toBe(`${path.join(workspaceWithDifferentDeps, 'packages/bar')}
+${path.join(workspaceWithDifferentDeps, 'packages/bar', 'node_modules/.pnpm/is-positive@3.1.0')}`
+  )
+})
+
 test('long parseable list with depth 1', async () => {
   expect(await list([fixture], { reportAs: 'parseable', depth: 1, lockfileDir: fixture, long: true })).toBe(`${fixture}:fixture@1.0.0
 ${path.join(fixture, 'node_modules/.pnpm/detect-indent@5.0.0')}:detect-indent@5.0.0