Allow to attribute changesets to merge commits

.changeset/clean-ghosts-leave.md

@@ -0,0 +1,8 @@
+---
+"@changesets/apply-release-plan": minor
+"@changesets/config": minor
+"@changesets/types": minor
+"@changesets/git": minor
+---
+
+Allow attributing changesets to merge commits

packages/apply-release-plan/src/index.ts

@@ -35,7 +35,8 @@ function stringDefined(s: string | undefined): s is string {
 }
 async function getCommitsThatAddChangesets(
   changesetIds: string[],
-  cwd: string
+  cwd: string,
+  useMergeCommits: boolean
 ) {
   const paths = changesetIds.map((id) => `.changeset/${id}.md`);
   const commits = await git.getCommitsThatAddFiles(paths, { cwd });
@@ -53,6 +54,7 @@ async function getCommitsThatAddChangesets(
   const legacyPaths = missingIds.map((id) => `.changeset/${id}/changes.json`);
   const commitsForLegacyPaths = await git.getCommitsThatAddFiles(legacyPaths, {
     cwd,
+    useMergeCommits,
   });
 
   // Fill in the blanks in the array of commits
@@ -230,7 +232,8 @@ async function getNewChangelogEntry(
 
   let commits = await getCommitsThatAddChangesets(
     changesets.map((cs) => cs.id),
-    cwd
+    cwd,
+    config.useMergeCommits
   );
   let moddedChangesets = changesets.map((cs, i) => ({
     ...cs,

packages/config/schema.json

@@ -75,6 +75,11 @@
       "description": "Determines whether Changesets should commit the results of the add and version command.",
       "default": false
     },
+    "useMergeCommits": {
+      "type": "boolean",
+      "description": "Determines whether changesets should be attributed to merge commits.",
+      "default": false
+    },
     "privatePackages": {
       "anyOf": [
         {

packages/config/src/index.test.ts

@@ -43,6 +43,7 @@ test("read reads the config", async () => {
     linked: [],
     changelog: false,
     commit: ["@changesets/cli/commit", { skipCI: "version" }],
+    useMergeCommits: false,
     access: "restricted",
     baseBranch: "master",
     changedFilePatterns: ["**"],
@@ -69,6 +70,7 @@ let defaults: Config = {
   linked: [],
   changelog: ["@changesets/cli/changelog", null],
   commit: false,
+  useMergeCommits: false,
   access: "restricted",
   baseBranch: "master",
   changedFilePatterns: ["**"],

packages/config/src/index.ts

@@ -431,6 +431,8 @@ export let parse = (json: WrittenConfig, packages: Packages): Config => {
     commit: getNormalizedCommitOption(
       json.commit === undefined ? defaultWrittenConfig.commit : json.commit
     ),
+    useMergeCommits:
+      json.useMergeCommits === undefined ? false : json.useMergeCommits,
     fixed,
     linked,
     baseBranch:

packages/git/src/index.ts

@@ -63,7 +63,11 @@ export async function getDivergedCommit(cwd: string, ref: string) {
  */
 export async function getCommitsThatAddFiles(
   gitPaths: string[],
-  { cwd, short = false }: { cwd: string; short?: boolean }
+  {
+    cwd,
+    short = false,
+    useMergeCommits = false,
+  }: { cwd: string; short?: boolean; useMergeCommits?: boolean }
 ): Promise<(string | undefined)[]> {
   // Maps gitPath to commit SHA
   const map = new Map<string, string>();
@@ -83,8 +87,9 @@ export async function getCommitsThatAddFiles(
               "--diff-filter=A",
               "--max-count=1",
               short ? "--pretty=format:%h:%p" : "--pretty=format:%H:%p",
+              useMergeCommits ? "--first-parent" : "",
               gitPath,
-            ],
+            ].filter(Boolean),
             { cwd }
           )
         ).stdout

packages/types/src/index.ts

@@ -69,6 +69,7 @@ export interface PrivatePackages {
 export type Config = {
   changelog: false | readonly [string, any];
   commit: false | readonly [string, any];
+  useMergeCommits: boolean;
   fixed: Fixed;
   linked: Linked;
   access: AccessType;
@@ -94,6 +95,7 @@ export type Config = {
 export type WrittenConfig = {
   changelog?: false | readonly [string, any] | string;
   commit?: boolean | readonly [string, any] | string;
+  useMergeCommits?: boolean;
   fixed?: Fixed;
   linked?: Linked;
   access?: AccessType;