Merge pull request #77 from zeebe-io/referred-issues

Referred issues placeholder

README.md

@@ -160,6 +160,7 @@ The following placeholders are available and are replaced with:
 
 Placeholder | Replaced with
 ------------|------------
+`issue_refs` | GitHub issue references to all issues mentioned in the original pull request description seperated by a space, e.g. `#123 #456 zeebe-io/backport-action#789`
 `pull_number` | The number of the original pull request that is backported, e.g. `123`
 `target_branch`| The branchname to which the pull request is backported, e.g. `release-0.23`
 

src/backport.ts

@@ -4,6 +4,7 @@ import dedent from "dedent";
 import { CreatePullRequestResponse, RequestReviewersResponse } from "./github";
 import { GithubApi } from "./github";
 import * as exec from "./exec";
+import * as utils from "./utils";
 
 type PRContent = {
   title: string;
@@ -136,7 +137,8 @@ export class Backport {
           const { title, body } = this.composePRContent(
             target,
             mainpr.title,
-            pull_number
+            pull_number,
+            mainpr.body
           );
           const new_pr_response = await this.github.createPR({
             owner,
@@ -209,12 +211,15 @@ export class Backport {
   private composePRContent(
     target: string,
     issue_title: string,
-    issue_number: number
+    issue_number: number,
+    original_body: string
   ): PRContent {
     const title = `[Backport ${target}] ${issue_title}`;
+    const issues = utils.getMentionedIssueRefs(original_body);
     const body = this.config.pull.description
       .replace("${pull_number}", issue_number.toString())
-      .replace("${target_branch}", target);
+      .replace("${target_branch}", target)
+      .replace("${issue_refs}", issues.join(" "));
     return { title, body };
   }
 

src/github.ts

@@ -87,6 +87,7 @@ export class Github implements GithubApi {
 export type PullRequest = {
   number: number;
   title: string;
+  body: string;
   head: {
     sha: string;
   };

src/test/utils.test.ts

@@ -0,0 +1,152 @@
+import dedent from "dedent";
+import { getMentionedIssueRefs } from "../utils";
+
+describe("get mentioned issues", () => {
+  describe("returns an empty list", () => {
+    it("for an empty text", () => {
+      expect(getMentionedIssueRefs("")).toHaveLength(0);
+    });
+
+    it("for a text without mentioned issues", () => {
+      expect(getMentionedIssueRefs(text({}))).toHaveLength(0);
+    });
+
+    it("for a text with an issue reference as part of a word", () => {
+      expect(getMentionedIssueRefs(text({ part: "#123" }))).toHaveLength(0);
+    });
+
+    it("for a text with an external issue reference as part of a word", () => {
+      expect(
+        getMentionedIssueRefs(text({ part: "zeebe-io/zeebe#123" }))
+      ).toHaveLength(0);
+    });
+
+    it("for a text with an issue url as part of a word", () => {
+      expect(
+        getMentionedIssueRefs(
+          text({ part: "github.com/zeebe-io/backport-action/issues/123" })
+        )
+      ).toHaveLength(0);
+    });
+  });
+
+  describe("returns a single reference", () => {
+    it("for a text with an issue reference at the start", () => {
+      expect(getMentionedIssueRefs(text({ start: "#123" }))).toEqual(["#123"]);
+    });
+    it("for a text with an issue reference in the middle", () => {
+      expect(getMentionedIssueRefs(text({ middle: "#123" }))).toEqual(["#123"]);
+    });
+    it("for a text with an issue reference at the end", () => {
+      expect(getMentionedIssueRefs(text({ end: "#123" }))).toEqual(["#123"]);
+    });
+
+    it("for a text with an external issue reference at the start", () => {
+      expect(
+        getMentionedIssueRefs(text({ start: "zeebe-io/zeebe#123" }))
+      ).toEqual(["zeebe-io/zeebe#123"]);
+    });
+    it("for a text with an external issue reference in the middle", () => {
+      expect(
+        getMentionedIssueRefs(text({ middle: "zeebe-io/zeebe#123" }))
+      ).toEqual(["zeebe-io/zeebe#123"]);
+    });
+    it("for a text with an external issue reference at the end", () => {
+      expect(
+        getMentionedIssueRefs(text({ end: "zeebe-io/zeebe#123" }))
+      ).toEqual(["zeebe-io/zeebe#123"]);
+    });
+
+    it("for a text with an issue url at the start", () => {
+      expect(
+        getMentionedIssueRefs(
+          text({ start: "github.com/zeebe-io/backport-action/issues/123/" })
+        )
+      ).toEqual(["zeebe-io/backport-action#123"]);
+    });
+    it("for a text with an issue url in the middle", () => {
+      expect(
+        getMentionedIssueRefs(
+          text({ middle: "github.com/zeebe-io/backport-action/issues/123" })
+        )
+      ).toEqual(["zeebe-io/backport-action#123"]);
+    });
+    it("for a text with an issue url at the end", () => {
+      expect(
+        getMentionedIssueRefs(
+          text({ end: "github.com/zeebe-io/backport-action/issues/123" })
+        )
+      ).toEqual(["zeebe-io/backport-action#123"]);
+    });
+  });
+
+  describe("returns all references", () => {
+    it("for a text with an issue reference at the start, middle and end", () => {
+      expect(
+        getMentionedIssueRefs(
+          text({ start: "#123", middle: "#234", end: "#345" })
+        )
+      ).toEqual(["#123", "#234", "#345"]);
+    });
+    it("for a text with an external issue reference at the start, middle and end", () => {
+      expect(
+        getMentionedIssueRefs(
+          text({
+            start: "zeebe-io/zeebe#123",
+            middle: "zeebe-io/zeebe#234",
+            end: "zeebe-io/zeebe#345",
+          })
+        )
+      ).toEqual([
+        "zeebe-io/zeebe#123",
+        "zeebe-io/zeebe#234",
+        "zeebe-io/zeebe#345",
+      ]);
+    });
+    it("for a text with an issue url at the start, middle and end", () => {
+      const base = "github.com/zeebe-io/backport-action/issues/";
+      expect(
+        getMentionedIssueRefs(
+          text({ start: `${base}123`, middle: `${base}234`, end: `${base}345` })
+        )
+      ).toEqual([
+        "zeebe-io/backport-action#123",
+        "zeebe-io/backport-action#234",
+        "zeebe-io/backport-action#345",
+      ]);
+    });
+    it("for a text with an external issue url at the start, middle and end", () => {
+      const base = "github.com/zeebe-io/zeebe/issues/";
+      expect(
+        getMentionedIssueRefs(
+          text({ start: `${base}123`, middle: `${base}234`, end: `${base}345` })
+        )
+      ).toEqual([
+        "zeebe-io/zeebe#123",
+        "zeebe-io/zeebe#234",
+        "zeebe-io/zeebe#345",
+      ]);
+    });
+  });
+
+  // todo deal with urls to unrelated repos
+});
+
+function text({
+  start = "",
+  middle = "",
+  end = "",
+  part = "",
+}: {
+  start?: string;
+  middle?: string;
+  end?: string;
+  part?: string;
+}) {
+  return dedent`${start ?? ""} foo bar
+                bar bar ${middle ?? ""} bar 
+
+                foo/${part ?? ""} foo${part ?? ""}foo ${part ?? ""}foo
+                
+                foo bar bar foo ${end ?? ""}`;
+}

src/utils.ts

@@ -0,0 +1,43 @@
+const patterns = {
+  // matches urls to github issues at start, middle, end of line as individual word
+  // may be lead and trailed by whitespace which should be trimmed
+  // captures the `org`, `repo` and `number` of the issue
+  // https://regex101.com/r/XKRl8q/5
+  url: {
+    global:
+      /(?:^| )(?:(?:https:\/\/)?(?:www\.)?github\.com\/(?<org>[^ \/\n]+)\/(?<repo>[^ \/\n]+)\/issues\/(?<number>[0-9]+)(?:\/)?)(?: |$)/gm,
+    first:
+      /(?:^| )(?:(?:https:\/\/)?(?:www\.)?github\.com\/(?<org>[^ \/\n]+)\/(?<repo>[^ \/\n]+)\/issues\/(?<number>[0-9]+)(?:\/)?)(?: |$)/m,
+  },
+
+  // matches `#123` at start, middle, end of line as individual word
+  // may be lead and trailed by whitespace which should be trimmed
+  // captures `number` of the issue (and optionally the `org` and `repo`)
+  // https://regex101.com/r/2gAB8O/2
+  ref: /(?:^| )((?<org>[^\n #\/]+)\/(?<repo>[^\n #\/]+))?#(?<number>[0-9]+)(?: |$)/gm,
+};
+
+/**
+ * @param body Text in which to search for mentioned issues
+ * @returns All found mentioned issues as GitHub issue references
+ */
+export function getMentionedIssueRefs(body: string): string[] {
+  const issueUrls =
+    body.match(patterns.url.global)?.map((url) => toRef(url)) ?? [];
+  const issueRefs = body.match(patterns.ref) ?? [];
+  return issueUrls.concat(issueRefs).map((ref) => ref.trim());
+}
+
+const toRef = (url: string) => {
+  // matchAll is not yet available to directly access the captured groups of all matches
+  // so this maps the urls to GitHub refs by matching again without the global flag
+  const result = patterns.url.first.exec(url);
+  if (!result) {
+    console.error(
+      `Expected to transform url (${url}) to GitHub reference, but it did not match pattern'`
+    );
+    return "";
+  }
+  const [, org, repo, number] = result;
+  return `${org}/${repo}#${number}`;
+};