Updates tests for the merge conflict resolution v5 (#6892)

## What's the problem this PR addresses?

This PR updates the tests to account for changes in the v5+ releases,
which will use `--theirs` as merge conflict resolution strategy to fix
bugs in which users could end up erasing changes from the upstream
branch when merging their own changes (due to us trying to override
existing ranges).

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Author: arcanis

packages/acceptance-tests/pkg-tests-core/sources/utils/tests.ts

@@ -38,6 +38,7 @@ function isAtLeastMajor(major: number) {
 export const FEATURE_CHECKS = {
   jsonLockfile: isAtLeastMajor(5),
   prologConstraints: !isAtLeastMajor(5),
+  mergeConflictTheirs: isAtLeastMajor(5),
 } as const;
 
 // Testing things inside a big-endian container takes forever

packages/acceptance-tests/pkg-tests-specs/sources/features/__snapshots__/mergeConflictResolution.test.ts.snap

@@ -1,173 +1,23 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`Features Merge Conflict Resolution it should properly fix merge conflicts 1`] = `
-"# This file is generated by running "yarn install" inside your project.
-# Manual changes might be lost - proceed with caution!
-
-__metadata:
-  version: X
-  cacheKey: 0c0
-
-"no-deps@npm:*":
-<<<<<<< HEAD
-  version: 1.0.0
-  resolution: "no-deps@npm:1.0.0"
-  checksum: <checksum stripped>
-=======
-  version: 2.0.0
-  resolution: "no-deps@npm:2.0.0"
-  checksum: <checksum stripped>
->>>>>>> 2.0.0
-  languageName: node
-  linkType: hard
-
-"root-workspace-0b6124@workspace:.":
-  version: 0.0.0-use.local
-  resolution: "root-workspace-0b6124@workspace:."
-  dependencies:
-    no-deps: "npm:*"
-  languageName: unknown
-  linkType: soft
-"
-`;
-
-exports[`Features Merge Conflict Resolution it should properly fix merge conflicts 2`] = `
-{
-  "code": 0,
-  "stderr": "",
-  "stdout": "➤ YN0048: Automatically fixed merge conflicts 👍
-
-➤ YN0000: · Yarn 0.0.0
-➤ YN0000: ┌ Resolution step
-➤ YN0000: └ Completed
-➤ YN0000: ┌ Fetch step
-➤ YN0013: │ No new packages added to the project, but one was removed (- 0.78 KiB).
-➤ YN0000: └ Completed
-➤ YN0000: ┌ Link step
-➤ YN0000: └ Completed
-➤ YN0000: · Done
-",
-}
-`;
-
 exports[`Features Merge Conflict Resolution it should properly fix merge conflicts when old is Yarn 1 and new is Yarn 2 1`] = `
 "# This file is generated by running "yarn install" inside your project.
 # Manual changes might be lost - proceed with caution!
 
-__metadata:
-  version: X
-  cacheKey: 0c0
-
 <<<<<<< HEAD
 no-deps@*:
   version "2.0.0"
   resolved "http://localhost:64572/no-deps/-/no-deps-2.0.0.tgz#f3b8f24d76b21b04748e6888672752b872236fa7"
   integrity sha1-87jyTXayGwR0jmiIZydSuHIjb6c=
 =======
-"no-deps@npm:*":
-  version: 2.0.0
-  resolution: "no-deps@npm:2.0.0"
-  checksum: <checksum stripped>
-  languageName: node
-  linkType: hard
-
-"root-workspace-0b6124@workspace:.":
-  version: 0.0.0-use.local
-  resolution: "root-workspace-0b6124@workspace:."
-  dependencies:
-    no-deps: "npm:*"
-  languageName: unknown
-  linkType: soft
->>>>>>> yarn2
-"
-`;
-
-exports[`Features Merge Conflict Resolution it should properly fix merge conflicts when old is Yarn 1 and new is Yarn 2 2`] = `
-{
-  "code": 0,
-  "stderr": "",
-  "stdout": "➤ YN0048: Automatically fixed merge conflicts 👍
-
-➤ YN0000: · Yarn 0.0.0
-➤ YN0000: ┌ Resolution step
-➤ YN0000: └ Completed
-➤ YN0000: ┌ Fetch step
-➤ YN0000: └ Completed
-➤ YN0000: ┌ Link step
-➤ YN0000: └ Completed
-➤ YN0000: · Done
-",
-}
-`;
-
-exports[`Features Merge Conflict Resolution it should support fixing cherry-pick conflicts 1`] = `
-"# This file is generated by running "yarn install" inside your project.
-# Manual changes might be lost - proceed with caution!
-
-__metadata:
-  version: X
-  cacheKey: 0c0
-
-"no-deps@npm:*":
-<<<<<<< HEAD
-  version: 1.0.0
-  resolution: "no-deps@npm:1.0.0"
-  checksum: <checksum stripped>
-=======
-  version: 2.0.0
-  resolution: "no-deps@npm:2.0.0"
-  checksum: <checksum stripped>
->>>>>>> 0000000 (commit-2.0.0)
-  languageName: node
-  linkType: hard
-
-"root-workspace-0b6124@workspace:.":
-  version: 0.0.0-use.local
-  resolution: "root-workspace-0b6124@workspace:."
-  dependencies:
-    no-deps: "npm:*"
-  languageName: unknown
-  linkType: soft
-"
-`;
-
-exports[`Features Merge Conflict Resolution it should support fixing cherry-pick conflicts 2`] = `
-{
-  "code": 0,
-  "stderr": "",
-  "stdout": "➤ YN0048: Automatically fixed merge conflicts 👍
-
-➤ YN0000: · Yarn 0.0.0
-➤ YN0000: ┌ Resolution step
-➤ YN0000: └ Completed
-➤ YN0000: ┌ Fetch step
-➤ YN0013: │ No new packages added to the project, but one was removed (- 0.78 KiB).
-➤ YN0000: └ Completed
-➤ YN0000: ┌ Link step
-➤ YN0000: └ Completed
-➤ YN0000: · Done
-",
-}
-`;
-
-exports[`Features Merge Conflict Resolution it should support fixing rebase conflicts 1`] = `
-"# This file is generated by running "yarn install" inside your project.
-# Manual changes might be lost - proceed with caution!
-
 __metadata:
   version: X
   cacheKey: 0c0
 
 "no-deps@npm:*":
-<<<<<<< HEAD
-  version: 2.0.0
-  resolution: "no-deps@npm:2.0.0"
-  checksum: <checksum stripped>
-=======
   version: 1.0.0
   resolution: "no-deps@npm:1.0.0"
   checksum: <checksum stripped>
->>>>>>> 0000000 (commit-1.0.0)
   languageName: node
   linkType: hard
 
@@ -178,10 +28,11 @@ __metadata:
     no-deps: "npm:*"
   languageName: unknown
   linkType: soft
+>>>>>>> yarn2
 "
 `;
 
-exports[`Features Merge Conflict Resolution it should support fixing rebase conflicts 2`] = `
+exports[`Features Merge Conflict Resolution it should properly fix merge conflicts when old is Yarn 1 and new is Yarn 2 2`] = `
 {
   "code": 0,
   "stderr": "",
@@ -191,7 +42,6 @@ exports[`Features Merge Conflict Resolution it should support fixing rebase conf
 ➤ YN0000: ┌ Resolution step
 ➤ YN0000: └ Completed
 ➤ YN0000: ┌ Fetch step
-➤ YN0013: │ No new packages added to the project, but one was removed (- 0.78 KiB).
 ➤ YN0000: └ Completed
 ➤ YN0000: ┌ Link step
 ➤ YN0000: └ Completed

packages/acceptance-tests/pkg-tests-specs/sources/features/mergeConflictResolution.test.ts

@@ -1,5 +1,5 @@
 import {Filename, ppath, xfs} from '@yarnpkg/fslib';
-import {exec}                 from 'pkg-tests-core';
+import {exec, tests}          from 'pkg-tests-core';
 
 const LOCKFILE_1_0_0 = `
 # THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
@@ -9,7 +9,7 @@ no-deps@*:
   version "1.0.0"
   resolved "http://localhost:64572/no-deps/-/no-deps-1.0.0.tgz#8d556c1e3e6c953ea16689c506073d5fa26b957f"
   integrity sha1-jVVsHj5slT6hZonFBgc9X6JrlX8=
-`;
+`.trimStart();
 
 const LOCKFILE_2_0_0 = `
 # THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
@@ -19,7 +19,7 @@ no-deps@*:
   version "2.0.0"
   resolved "http://localhost:64572/no-deps/-/no-deps-2.0.0.tgz#f3b8f24d76b21b04748e6888672752b872236fa7"
   integrity sha1-87jyTXayGwR0jmiIZydSuHIjb6c=
-`;
+`.trimStart();
 
 function cleanLockfile(lockfile: string) {
   lockfile = lockfile.replace(/(^ {2}version: )[0-9]+$/m, `$1X`);
@@ -51,25 +51,61 @@ describe(`Features`, () => {
 
           await exec.execFile(`git`, [`checkout`, `master`], {cwd: path});
           await exec.execFile(`git`, [`checkout`, `-b`, `1.0.0`], {cwd: path});
+
           await run(`set`, `resolution`, `no-deps@npm:*`, `npm:1.0.0`);
+          const expectedV1Lockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+
           await exec.execFile(`git`, [`add`, `-A`], {cwd: path});
           await exec.execFile(`git`, [`commit`, `-a`, `-m`, `commit-1.0.0`], {cwd: path});
 
           await exec.execFile(`git`, [`checkout`, `master`], {cwd: path});
           await exec.execFile(`git`, [`checkout`, `-b`, `2.0.0`], {cwd: path});
+
           await run(`set`, `resolution`, `no-deps@npm:*`, `npm:2.0.0`);
+          const expectedV2Lockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+
           await exec.execFile(`git`, [`add`, `-A`], {cwd: path});
           await exec.execFile(`git`, [`commit`, `-a`, `-m`, `commit-2.0.0`], {cwd: path});
 
-          await exec.execFile(`git`, [`checkout`, `master`], {cwd: path});
-          await exec.execFile(`git`, [`merge`, `1.0.0`], {cwd: path});
+          /* Merging 1.0 first, then 2.0 */{
+            await exec.execFile(`git`, [`checkout`, `-b`, `merge-1-then-2`, `master`], {cwd: path});
+            await exec.execFile(`git`, [`merge`, `1.0.0`], {cwd: path});
 
-          await expect(exec.execFile(`git`, [`merge`, `2.0.0`], {cwd: path, env: {LC_ALL: `C`}})).rejects.toThrow(/CONFLICT/);
+            await expect(exec.execFile(`git`, [`merge`, `2.0.0`], {cwd: path, env: {LC_ALL: `C`}})).rejects.toThrow(/CONFLICT/);
 
-          const lockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
-          expect(cleanLockfile(lockfile)).toMatchSnapshot();
+            const preFixLockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+            expect(preFixLockfile).toContain(`<<<<<<<`);
 
-          await expect(run(`install`)).resolves.toMatchSnapshot();
+            await run(`install`);
+
+            const expectedLockfile = tests.FEATURE_CHECKS.mergeConflictTheirs
+              ? expectedV2Lockfile
+              : expectedV1Lockfile;
+
+            const postFixLockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+            expect(postFixLockfile).toEqual(expectedLockfile);
+
+            await exec.execFile(`git`, [`merge`, `--abort`], {cwd: path});
+          }
+
+          /* Merging 2.0 first, then 1.0 */ {
+            await exec.execFile(`git`, [`checkout`, `-b`, `merge-2-then-1`, `master`], {cwd: path});
+            await exec.execFile(`git`, [`merge`, `2.0.0`], {cwd: path});
+
+            await expect(exec.execFile(`git`, [`merge`, `1.0.0`], {cwd: path, env: {LC_ALL: `C`}})).rejects.toThrow(/CONFLICT/);
+
+            const preFixLockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+            expect(preFixLockfile).toContain(`<<<<<<<`);
+
+            await run(`install`);
+
+            const expectedLockfile = tests.FEATURE_CHECKS.mergeConflictTheirs
+              ? expectedV1Lockfile
+              : expectedV2Lockfile;
+
+            const postFixLockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+            expect(postFixLockfile).toEqual(expectedLockfile);
+          }
         },
       ),
     );
@@ -127,13 +163,18 @@ describe(`Features`, () => {
 
           await exec.execFile(`git`, [`checkout`, `master`], {cwd: path});
           await exec.execFile(`git`, [`checkout`, `-b`, `1.0.0`], {cwd: path});
+
           await run(`set`, `resolution`, `no-deps@npm:*`, `npm:1.0.0`);
+
           await exec.execFile(`git`, [`add`, `-A`], {cwd: path});
           await exec.execFile(`git`, [`commit`, `-a`, `-m`, `commit-1.0.0`], {cwd: path});
 
           await exec.execFile(`git`, [`checkout`, `master`], {cwd: path});
           await exec.execFile(`git`, [`checkout`, `-b`, `2.0.0`], {cwd: path});
+
           await run(`set`, `resolution`, `no-deps@npm:*`, `npm:2.0.0`);
+          const expectedV2Lockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+
           await exec.execFile(`git`, [`add`, `-A`], {cwd: path});
           await exec.execFile(`git`, [`commit`, `-a`, `-m`, `commit-2.0.0`], {cwd: path});
 
@@ -142,10 +183,13 @@ describe(`Features`, () => {
 
           await expect(exec.execFile(`git`, [`rebase`, `2.0.0`], {cwd: path, env: {LC_ALL: `C`}})).rejects.toThrow(/CONFLICT/);
 
-          const lockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
-          expect(cleanLockfile(lockfile)).toMatchSnapshot();
+          const preFixLockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+          expect(preFixLockfile).toContain(`<<<<<<<`);
 
-          await expect(run(`install`)).resolves.toMatchSnapshot();
+          await run(`install`);
+
+          const postFixLockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+          expect(postFixLockfile).toEqual(expectedV2Lockfile);
         },
       ),
     );
@@ -165,13 +209,19 @@ describe(`Features`, () => {
 
           await exec.execFile(`git`, [`checkout`, `master`], {cwd: path});
           await exec.execFile(`git`, [`checkout`, `-b`, `1.0.0`], {cwd: path});
+
           await run(`set`, `resolution`, `no-deps@npm:*`, `npm:1.0.0`);
+          const expectedV1Lockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+
           await exec.execFile(`git`, [`add`, `-A`], {cwd: path});
           await exec.execFile(`git`, [`commit`, `-a`, `-m`, `commit-1.0.0`], {cwd: path});
 
           await exec.execFile(`git`, [`checkout`, `master`], {cwd: path});
           await exec.execFile(`git`, [`checkout`, `-b`, `2.0.0`], {cwd: path});
+
           await run(`set`, `resolution`, `no-deps@npm:*`, `npm:2.0.0`);
+          const expectedV2Lockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+
           await exec.execFile(`git`, [`add`, `-A`], {cwd: path});
           await exec.execFile(`git`, [`commit`, `-a`, `-m`, `commit-2.0.0`], {cwd: path});
 
@@ -180,10 +230,17 @@ describe(`Features`, () => {
 
           await expect(exec.execFile(`git`, [`cherry-pick`, `2.0.0`], {cwd: path, env: {LC_ALL: `C`}})).rejects.toThrow(/CONFLICT/);
 
-          const lockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
-          expect(cleanLockfile(lockfile)).toMatchSnapshot();
+          const preFixLockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+          expect(preFixLockfile).toContain(`<<<<<<<`);
 
-          await expect(run(`install`)).resolves.toMatchSnapshot();
+          await run(`install`);
+
+          const expectedLockfile = tests.FEATURE_CHECKS.mergeConflictTheirs
+            ? expectedV2Lockfile
+            : expectedV1Lockfile;
+
+          const postFixLockfile = await xfs.readFilePromise(ppath.join(path, Filename.lockfile), `utf8`);
+          expect(postFixLockfile).toEqual(expectedLockfile);
         },
       ),
     );