feat(cascading): option to bypass non-latest minor branch (#2473)

## Proposed change

Option to bypass non-latest minor branch on cascading bot

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.github/.cascadingrc.json

@@ -1,6 +1,5 @@
 {
   "$schema": "../apps/github-cascading-app/schemas/config.schema.json",
-  "bypassReviewers": true,
   "labels": ["cascading"],
   "ignoredPatterns": [
     "-next$"

apps/github-cascading-app/schemas/config.schema.json

@@ -31,6 +31,11 @@
       "description": "Pattern determining if the branch is part of the cascading strategy",
       "default": "^releases?/\\d+\\.\\d+"
     },
+    "onlyCascadeOnHighestMinors": {
+      "type": "boolean",
+      "description": "Determine if the branches for which a higher minor version exists should be skipped during the cascading",
+      "default": false
+    },
     "versionCapturePattern": {
       "type": "string",
       "description": "Pattern containing a capture to extract the version of a cascading branch",

apps/github-cascading-app/src/cascading/cascading.spec.ts

@@ -207,6 +207,91 @@ describe('Cascading Application', () => {
       expect(logger.info).toHaveBeenCalledWith('The branch test-cascading/1.0 is the last branch of the cascading. The process will stop.');
     });
 
+    describe('on onlyCascadeOnHighestMinors options', () => {
+      it('should ignore branches not to the latest minor when true', async () => {
+        customization.loadConfiguration = customization.loadConfiguration.mockResolvedValue({
+          ...DEFAULT_CONFIGURATION,
+          cascadingBranchesPattern: 'test-cascading/.*',
+          onlyCascadeOnHighestMinors: true,
+          ignoredPatterns: []
+        });
+        customization.getBranches = customization.getBranches.mockResolvedValue([
+          'test-cascading/1.0',
+          'test-cascading/1.1',
+          'test-cascading/1.2',
+          'test-cascading/2.0'
+        ]);
+        customization.isBranchAhead = customization.isBranchAhead.mockResolvedValue(true);
+        customization.createBranch = customization.createBranch.mockResolvedValue();
+        customization.getPullRequests = customization.getPullRequests.mockResolvedValue([]);
+        customization.createPullRequest = customization.createPullRequest.mockResolvedValue({
+          id: 1,
+          originBranchName: '',
+          isOpen: true,
+          mergeable: true,
+          body: render(mockBasicTemplate, { isConflicting: false, targetBranch: 'main', currentBranch: 'release/0.1', bypassReviewers: true }, { async: false })
+        });
+        await expect(customization.cascade('test-cascading/1.0')).resolves.not.toThrow();
+        expect(logger.info).toHaveBeenCalledWith('Cascading plugin execution');
+        expect(customization.isBranchAhead).toHaveBeenCalledWith('test-cascading/1.0', 'test-cascading/1.2');
+      });
+
+      it('should ignore branches until latest if needed', async () => {
+        customization.loadConfiguration = customization.loadConfiguration.mockResolvedValue({
+          ...DEFAULT_CONFIGURATION,
+          cascadingBranchesPattern: 'test-cascading/.*',
+          onlyCascadeOnHighestMinors: true,
+          defaultBranch: 'main',
+          ignoredPatterns: []
+        });
+        customization.getBranches = customization.getBranches.mockResolvedValue([
+          'test-cascading/1.0',
+          'main'
+        ]);
+        customization.isBranchAhead = customization.isBranchAhead.mockResolvedValue(true);
+        customization.createBranch = customization.createBranch.mockResolvedValue();
+        customization.getPullRequests = customization.getPullRequests.mockResolvedValue([]);
+        customization.createPullRequest = customization.createPullRequest.mockResolvedValue({
+          id: 1,
+          originBranchName: '',
+          isOpen: true,
+          mergeable: true,
+          body: render(mockBasicTemplate, { isConflicting: false, targetBranch: 'main', currentBranch: 'release/0.1', bypassReviewers: true }, { async: false })
+        });
+        await expect(customization.cascade('test-cascading/1.0')).resolves.not.toThrow();
+        expect(logger.info).toHaveBeenCalledWith('Cascading plugin execution');
+        expect(customization.isBranchAhead).toHaveBeenCalledWith('test-cascading/1.0', 'main');
+      });
+
+      it('should consider branches not to the latest minor when false', async () => {
+        customization.loadConfiguration = customization.loadConfiguration.mockResolvedValue({
+          ...DEFAULT_CONFIGURATION,
+          cascadingBranchesPattern: 'test-cascading/.*',
+          onlyCascadeOnHighestMinors: false,
+          ignoredPatterns: []
+        });
+        customization.getBranches = customization.getBranches.mockResolvedValue([
+          'test-cascading/1.0',
+          'test-cascading/1.1',
+          'test-cascading/1.2',
+          'test-cascading/2.0'
+        ]);
+        customization.isBranchAhead = customization.isBranchAhead.mockResolvedValue(true);
+        customization.createBranch = customization.createBranch.mockResolvedValue();
+        customization.getPullRequests = customization.getPullRequests.mockResolvedValue([]);
+        customization.createPullRequest = customization.createPullRequest.mockResolvedValue({
+          id: 1,
+          originBranchName: '',
+          isOpen: true,
+          mergeable: true,
+          body: render(mockBasicTemplate, { isConflicting: false, targetBranch: 'main', currentBranch: 'release/0.1', bypassReviewers: true }, { async: false })
+        });
+        await expect(customization.cascade('test-cascading/1.0')).resolves.not.toThrow();
+        expect(logger.info).toHaveBeenCalledWith('Cascading plugin execution');
+        expect(customization.isBranchAhead).toHaveBeenCalledWith('test-cascading/1.0', 'test-cascading/1.1');
+      });
+    });
+
     it('should skip ignored branch if not ahead', async () => {
       customization.loadConfiguration = customization.loadConfiguration.mockResolvedValue({
         ...DEFAULT_CONFIGURATION,

apps/github-cascading-app/src/cascading/cascading.ts

@@ -7,7 +7,9 @@ import {
 import {
   coerce,
   compare,
+  lte,
   parse,
+  type SemVer,
   valid,
 } from 'semver';
 import {
@@ -30,6 +32,9 @@ export const CASCADING_BRANCH_PREFIX = 'cascading';
 /** Time (in ms) to wait before re-checking the mergeable status of a PR */
 export const RETRY_MERGEAGLE_STATUS_CHECK_TIMING = 3000;
 
+/** Object representing a branch with the version determined from its name */
+type BranchObject = { branch: string; semver: SemVer | undefined };
+
 /**
  * Handles the cascading to the next branch
  */
@@ -184,7 +189,8 @@ export abstract class Cascading {
           };
         }
       })
-      .filter(({ branch, semver }) => {
+      .filter((branchObject): branchObject is BranchObject => {
+        const { branch, semver } = branchObject;
         if (semver === null) {
           this.logger.warn(`Failed to parse the branch ${branch}, it will be skipped from cascading`);
           return false;
@@ -206,7 +212,7 @@ export abstract class Cascading {
   }
 
   /**
-   * Generate teh cascading branch name
+   * Generate the cascading branch name
    * @param baseVersion Version extracted from the base branch
    * @param targetVersion Version extracted from the target branch
    * @param configurations
@@ -352,6 +358,36 @@ export abstract class Cascading {
     return !checkboxLine?.[0]?.match(/^ *- \[x]/i);
   }
 
+  protected getTargetBranch(cascadingBranches: BranchObject[], currentBranchName: string, config: CascadingConfiguration) {
+    const branchIndex = cascadingBranches.findIndex(({ branch }) => branch === currentBranchName);
+    if (branchIndex === -1) {
+      this.logger.error(`The branch ${currentBranchName} is not part of the list of cascading branch. The process will stop.`);
+      return;
+    }
+
+    if (branchIndex === cascadingBranches.length - 1) {
+      this.logger.info(`The branch ${currentBranchName} is the last branch of the cascading. The process will stop.`);
+      return;
+    }
+
+    const targetBranchIndex = branchIndex + 1;
+    if (!config.onlyCascadeOnHighestMinors) {
+      return cascadingBranches[targetBranchIndex];
+    }
+
+    for (let i = targetBranchIndex; i < cascadingBranches.length; i++) {
+      const targetBranch = cascadingBranches[i];
+      const { semver } = targetBranch;
+      if (!semver) {
+        return targetBranch;
+      }
+
+      if (cascadingBranches.slice(i + 1).every((otherBranch) => otherBranch.semver?.major !== semver.major || (otherBranch.semver && lte(otherBranch.semver, semver)))) {
+        return targetBranch;
+      }
+    }
+  }
+
   /**
    * Launch the cascading process
    * @param currentBranchName name of the branch to cascade (ex: release/8.0)
@@ -377,20 +413,14 @@ export abstract class Cascading {
     this.logger.info('Cascading plugin execution');
     const branches = await this.getBranches();
     const cascadingBranches = this.getOrderedCascadingBranches(branches, config);
-    const branchIndex = cascadingBranches.findIndex(({ branch }) => branch === currentBranchName);
+    const targetBranch = this.getTargetBranch(cascadingBranches, currentBranchName, config);
 
-    if (branchIndex === -1) {
-      this.logger.error(`The branch ${currentBranchName} is not part of the list of cascading branch. The process will stop.`);
-      return;
-    }
-
-    if (branchIndex === cascadingBranches.length - 1) {
-      this.logger.info(`The branch ${currentBranchName} is the last branch of the cascading. The process will stop.`);
+    if (!targetBranch) {
+      this.logger.info(`No target branch found for the cascading from ${currentBranchName}. The process will stop.`);
       return;
     }
 
-    const currentBranch = cascadingBranches[branchIndex];
-    const targetBranch = cascadingBranches[branchIndex + 1];
+    const currentBranch = cascadingBranches.find(({ branch }) => branch === currentBranchName)!;
     const cascadingBranch = this.determineCascadingBranchName(currentBranch.semver?.format() || currentBranch.branch, targetBranch.semver?.format() || targetBranch.branch, config);
     const isAhead = await this.isBranchAhead(currentBranch.branch, targetBranch.branch);
 

apps/github-cascading-app/src/cascading/interfaces.ts

@@ -11,6 +11,8 @@ export interface CascadingConfiguration {
   defaultBranch: string;
   /** Pattern determining if the branch is part of the cascading strategy */
   cascadingBranchesPattern: string;
+  /** Determine if the branches for which a higher minor version exists should be skipped during the cascading */
+  onlyCascadeOnHighestMinors: boolean;
   /** Pattern containing a capture to extract the version of a cascading branch */
   versionCapturePattern: string;
   /** Bypass the reviewers validation for the pull request, only the CI checks will be executed */
@@ -34,7 +36,10 @@ export interface PullRequestContext {
   currentBranch: string;
   /** Cascading Pull Request Target Branch */
   targetBranch: string;
-  /** Determine if the reviewers are bypassed */
+  /**
+   * Determine if the reviewers are bypassed
+   * Note: This option is not supported on Github anymore due to Github Api change.
+   */
   bypassReviewers: boolean;
   /** Is the an update of the {@link currentBranch} conflicting */
   isConflicting: boolean;
@@ -68,6 +73,7 @@ export const DEFAULT_CONFIGURATION: Readonly<CascadingConfiguration> = {
   ignoredPatterns: [] as string[],
   defaultBranch: '',
   cascadingBranchesPattern: '^releases?/\\d+\\.\\d+',
+  onlyCascadeOnHighestMinors: false,
   versionCapturePattern: '/((?:0|[1-9]\\d*)\\.(?:0|[1-9]\\d*)(?:\\.0-[^ ]+)?)$',
   bypassReviewers: false,
   labels: [] as string[],