Merging

Template producer functions return Creation objects. When a --mode is specified, a template may run multiple producer functions. The two creations from those producer functions will need to be merged together.

Each type of creation has its own merging logic:

• files
• requests
• scripts
• suggestions

Files

File objects are recursively merged:

• false and undefined values are ignored
• Files are deduplicated if they have the same value, and an error is thrown if they do not

For example, given the following two files Creations to be merged:

{
   "LICENSE.txt": "# MIT",
   src: {
      "index.ts": `export * from "./types.ts"`,
   },
}

{
   "LICENSE.txt": "# MIT",
   src: {
      "types.ts": `export type Example = true;`,
   },
}

The merged result would be:

{
   "LICENSE.txt": "# MIT",
   src: {
      "index.ts": `export * from "./types.ts"`,
      "types.ts": `export type Example = true;`,
   },
}

Requests

Requests are merged base on their id and type: _ If two requests have different id values, they are always considered separate _ Otherwise, requests are merged based on their type: _ fetch requests have init merged with Object.assign() if they contain the same url _ octokit requests have parameters merged with Object.assign() if they contain the same endpoint

For example, the following two requests Creations would not be merged, because they have different endpoints:

[
  {
    endpoint: "POST /repos/{owner}/{repo}/autolinks",
    parameters: {
      key_prefix: "TICKET-",
      owner: "JoshuaKGoldberg",
      repo: "create-typescript-app",
      url_template: "https://example.com/TICKET?query=<num>",
    }
    type: "octokit",
  },
  {
    endpoint: "POST /repos/{owner}/{repo}/issues",
    parameters: {
      name: "good first issue",
      owner: "JoshuaKGoldberg",
      repo: "create-typescript-app",
    }
    type: "octokit",
  }
]

However, the following two requests Creations would be merged into one with the same endpoint:

[
  {
    endpoint: "POST /repos/{owner}/{repo}/issues",
    parameters: {
      color: "#ffcc00",
      name: "good first issue (pending color)",
      owner: "JoshuaKGoldberg",
      repo: "create-typescript-app",
    }
    type: "octokit",
  },
  {
    endpoint: "POST /repos/{owner}/{repo}/issues",
    parameters: {
      name: "good first issue",
      owner: "JoshuaKGoldberg",
      repo: "create-typescript-app",
    }
    type: "octokit",
  }
]

The merged result would be:

[
  {
    endpoint: "POST /repos/{owner}/{repo}/issues",
    parameters: {
      color: "#ffcc00",
      name: "good first issue",
      owner: "JoshuaKGoldberg",
      repo: "create-typescript-app",
    }
    type: "octokit",
  }
]

Scripts

Scripts are deduplicated based on whether they include a phase:

• “Phase” scripts are deduplicated if any’s arrays of commands are the same as any other
• “Standalone” scripts provided as string are deduplicated and run in parallel after scripts with phases

For example, given the following two scripts Creations to be merged:

[
  {
    commands: ["pnpm install", "pnpm dedupe"],
    phase: 0,
  },
];

[
  `npx set-github-repository-labels --labels "$(cat labels.json)"`,
  {
    commands: ["pnpm install"],
    phase: 0,
  },
];

The merged result would be:

[
  {
    commands: ["pnpm install", "pnpm dedupe"],
    phase: 0,
  },
  `npx set-github-repository-labels --labels "$(cat labels.json)"`,
];

Suggestions

Suggestions are deduplicated by identity.

For example, given the following two suggestions Creations to be merged:

[
  "- set a CODECOV secret to an codecov repository token",
  "- set a NPM_TOKEN secret to an npm automation token",
];

[
  "- set an ACCESS_TOKEN secret to a GitHub PAT with repo and workflow permissions",
  "- set a NPM_TOKEN secret to an npm access token with automation permissions",
];

The merged result would be:

[
  "- set a CODECOV secret to an codecov repository token",
  "- set a NPM_TOKEN secret to an npm access token with automation permissions",
  "- set an ACCESS_TOKEN secret to a GitHub PAT with repo and workflow permissions",
];