GitHub Copilot 錦囊妙計：定義 Git 提交訊息產生的自訂指令

在 VS Code 的「原始碼控制」窗格中，不僅僅可以用來做 Git 版控，你還能利用 GitHub Copilot 來產生即將 Commit 的程式碼變更的提交訊息，透過 AI 幫你自動撰寫 Git 的 Log 內容。事實上，在新版的 GitHub Copilot 中，你可以透過定義「自訂指令」(Custom instructions) 來「提示」GitHub Copilot 要如何產生 Log 訊息內容，你可以自己定義擁有團隊共識或大家希望的 Commit Log 風格，例如可以套用 Conventional Commits 風格等等。這篇文章我就來說說怎麼做！👍

collaboration between GitHub Copilot and developers for generating consistent Git commit message

要完成這個任務，主要就以下三件事：

準備好提示內容
在 VS Code 中設定自訂指令
學會如何使用自訂指令寫 Git 提交訊息

1. 準備好提示內容

我在我公司已經有很多專案採用 Conventional Commits 風格來寫 Git 提交訊息，這樣可以讓我們的提交訊息更有結構，也方便後續的版本控制管理。不過，你也知道的，人性真的很難，文件寫在 Wiki 裡面，就是永遠有人不看，三不五時就是有人忘記套用這個風格寫 Commit Log！因此，我們可以透過自訂指令來提示 GitHub Copilot 產生符合這個風格的提交訊息。

還好 Conventional Commits 官網有提供完整的規格與範例，我們其實不用自己寫說明，這些網站中的內容恰好可以拿來當作提示內容，你只要把內容轉成 Markdown 文字格式即可。

準備步驟如下：

用瀏覽器打開 Conventional Commits 官網
直接按下 Ctrl+A 全選網頁內容，按下 Ctrl+C 複製
開啟我先前寫的 Paste to Markdown 工具 (這是一個網站)
開啟網頁後，直接按下 Ctrl+V 貼上，即可得到完整的 Markdown 內容
將這文件容移除一些網頁中頁首、選單、頁尾的內容，留下規格與範例部分即可

以下是我整理過的內容：

# Conventional Commits 1.0.0

## Summary

The Conventional Commits specification is a lightweight convention on top of commit messages. It provides an easy set of rules for creating an explicit commit history; which makes it easier to write automated tools on top of. This convention dovetails with [SemVer](http://semver.org/), by describing the features, fixes, and breaking changes made in commit messages.

The commit message should be structured as follows:

* * * * *

```
<type>[optional scope]: <description>

[optional body]

[optional footer(s)]
```

* * * * *

The commit contains the following structural elements, to communicate intent to the consumers of your library:

1. **fix:** a commit of the *type* `fix` patches a bug in your codebase (this correlates with [`PATCH`](http://semver.org/#summary) in Semantic Versioning).
2. **feat:** a commit of the *type* `feat` introduces a new feature to the codebase (this correlates with [`MINOR`](http://semver.org/#summary) in Semantic Versioning).
3. **BREAKING CHANGE:** a commit that has a footer `BREAKING CHANGE:`, or appends a `!` after the type/scope, introduces a breaking API change (correlating with [`MAJOR`](http://semver.org/#summary) in Semantic Versioning). A BREAKING CHANGE can be part of commits of any *type*.
4. *types* other than `fix:` and `feat:` are allowed, for example [@commitlint/config-conventional](https://github.com/conventional-changelog/commitlint/tree/master/%40commitlint/config-conventional) (based on the [Angular convention](https://github.com/angular/angular/blob/22b96b9/CONTRIBUTING.md#-commit-message-guidelines)) recommends `build:`, `chore:`, `ci:`, `docs:`, `style:`, `refactor:`, `perf:`, `test:`, and others.
5. *footers* other than `BREAKING CHANGE: <description>` may be provided and follow a convention similar to [git trailer format](https://git-scm.com/docs/git-interpret-trailers).

Additional types are not mandated by the Conventional Commits specification, and have no implicit effect in Semantic Versioning (unless they include a BREAKING CHANGE). A scope may be provided to a commit's type, to provide additional contextual information and is contained within parenthesis, e.g., `feat(parser): add ability to parse arrays`.

## Examples

### Commit message with description and breaking change footer

```
feat: allow provided config object to extend other configs

BREAKING CHANGE: `extends` key in config file is now used for extending other config files
```

### Commit message with `!` to draw attention to breaking change

```
feat!: send an email to the customer when a product is shipped
```

### Commit message with scope and `!` to draw attention to breaking change

```
feat(api)!: send an email to the customer when a product is shipped
```

### Commit message with both `!` and BREAKING CHANGE footer

```
chore!: drop support for Node 6

BREAKING CHANGE: use JavaScript features not available in Node 6.
```

### Commit message with no body

```
docs: correct spelling of CHANGELOG
```

### Commit message with scope

```
feat(lang): add Polish language
```

### Commit message with multi-paragraph body and multiple footers

```
fix: prevent racing of requests

Introduce a request id and a reference to latest request. Dismiss
incoming responses other than from latest request.

Remove timeouts which were used to mitigate the racing issue but are
obsolete now.

Reviewed-by: Z
Refs: #123
```

## Specification

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC 2119](https://www.ietf.org/rfc/rfc2119.txt).

1. Commits MUST be prefixed with a type, which consists of a noun, `feat`, `fix`, etc., followed by the OPTIONAL scope, OPTIONAL `!`, and REQUIRED terminal colon and space.
2. The type `feat` MUST be used when a commit adds a new feature to your application or library.
3. The type `fix` MUST be used when a commit represents a bug fix for your application.
4. A scope MAY be provided after a type. A scope MUST consist of a noun describing a section of the codebase surrounded by parenthesis, e.g., `fix(parser):`
5. A description MUST immediately follow the colon and space after the type/scope prefix. The description is a short summary of the code changes, e.g., *fix: array parsing issue when multiple spaces were contained in string*.
6. A longer commit body MAY be provided after the short description, providing additional contextual information about the code changes. The body MUST begin one blank line after the description.
7. A commit body is free-form and MAY consist of any number of newline separated paragraphs.
8. One or more footers MAY be provided one blank line after the body. Each footer MUST consist of a word token, followed by either a `:<space>` or `<space>#` separator, followed by a string value (this is inspired by the [git trailer convention](https://git-scm.com/docs/git-interpret-trailers)).
9. A footer's token MUST use `-` in place of whitespace characters, e.g., `Acked-by` (this helps differentiate the footer section from a multi-paragraph body). An exception is made for `BREAKING CHANGE`, which MAY also be used as a token.
10. A footer's value MAY contain spaces and newlines, and parsing MUST terminate when the next valid footer token/separator pair is observed.
11. Breaking changes MUST be indicated in the type/scope prefix of a commit, or as an entry in the footer.
12. If included as a footer, a breaking change MUST consist of the uppercase text BREAKING CHANGE, followed by a colon, space, and description, e.g., *BREAKING CHANGE: environment variables now take precedence over config files*.
13. If included in the type/scope prefix, breaking changes MUST be indicated by a `!` immediately before the `:`. If `!` is used, `BREAKING CHANGE:` MAY be omitted from the footer section, and the commit description SHALL be used to describe the breaking change.
14. Types other than `feat` and `fix` MAY be used in your commit messages, e.g., *docs: update ref docs.*
15. The units of information that make up Conventional Commits MUST NOT be treated as case sensitive by implementors, with the exception of BREAKING CHANGE which MUST be uppercase.
16. BREAKING-CHANGE MUST be synonymous with BREAKING CHANGE, when used as a token in a footer.

## Why Use Conventional Commits

- Automatically generating CHANGELOGs.
- Automatically determining a semantic version bump (based on the types of commits landed).
- Communicating the nature of changes to teammates, the public, and other stakeholders.
- Triggering build and publish processes.
- Making it easier for people to contribute to your projects, by allowing them to explore a more structured commit history.

## FAQ

### How should I deal with commit messages in the initial development phase?

We recommend that you proceed as if you've already released the product. Typically *somebody*, even if it's your fellow software developers, is using your software. They'll want to know what's fixed, what breaks etc.

### Are the types in the commit title uppercase or lowercase?

Any casing may be used, but it's best to be consistent.

### What do I do if the commit conforms to more than one of the commit types?

Go back and make multiple commits whenever possible. Part of the benefit of Conventional Commits is its ability to drive us to make more organized commits and PRs.

### Doesn't this discourage rapid development and fast iteration?

It discourages moving fast in a disorganized way. It helps you be able to move fast long term across multiple projects with varied contributors.

### Might Conventional Commits lead developers to limit the type of commits they make because they'll be thinking in the types provided?

Conventional Commits encourages us to make more of certain types of commits such as fixes. Other than that, the flexibility of Conventional Commits allows your team to come up with their own types and change those types over time.

### How does this relate to SemVer?

`fix` type commits should be translated to `PATCH` releases. `feat` type commits should be translated to `MINOR` releases. Commits with `BREAKING CHANGE` in the commits, regardless of type, should be translated to `MAJOR` releases.

### How should I version my extensions to the Conventional Commits Specification, e.g. `@jameswomack/conventional-commit-spec`?

We recommend using SemVer to release your own extensions to this specification (and encourage you to make these extensions!)

### What do I do if I accidentally use the wrong commit type?

#### When you used a type that's of the spec but not the correct type, e.g. `fix` instead of `feat`

Prior to merging or releasing the mistake, we recommend using `git rebase -i` to edit the commit history. After release, the cleanup will be different according to what tools and processes you use.

#### When you used a type *not* of the spec, e.g. `feet` instead of `feat`

In a worst case scenario, it's not the end of the world if a commit lands that does not meet the Conventional Commits specification. It simply means that commit will be missed by tools that are based on the spec.

### Do all my contributors need to use the Conventional Commits specification?

No! If you use a squash based workflow on Git lead maintainers can clean up the commit messages as they're merged---adding no workload to casual committers. A common workflow for this is to have your git system automatically squash commits from a pull request and present a form for the lead maintainer to enter the proper git commit message for the merge.

### How does Conventional Commits handle revert commits?

Reverting code can be complicated: are you reverting multiple commits? if you revert a feature, should the next release instead be a patch?

Conventional Commits does not make an explicit effort to define revert behavior. Instead we leave it to tooling authors to use the flexibility of *types* and *footers* to develop their logic for handling reverts.

One recommendation is to use the `revert` type, and a footer that references the commit SHAs that are being reverted:

```
revert: let us never again speak of the noodle incident

Refs: 676104e, a215868
```

2. 在 VS Code 中設定自訂指令

接著你在 VS Code 中，你可以透過調整 github.copilot.chat.commitMessageGeneration.instructions 設定 (Settings) 來定義 Copilot 幫你撰寫提交訊息的自訂指令，其設定如下：

"github.copilot.chat.commitMessageGeneration.instructions": [
  {
    "text": "<<請放入你整理好的自訂指令內容>>"
  },
  {
    "text": "請一律使用正體中文來撰寫記錄"
  }
],

這裡你應該會發現要把多行的 Markdown 文字放入一個 JSON 的字串中，其實有點難度，因為 JSON 字串不支援斷行，你要全部調整過才能塞入這個字串中。不過，我有好方法，你可以透過 JSON Escaper 幫我們做好這件事！

在 VS Code 中安裝 JSON Escaper 擴充功能
在 VS Code 中按下 Ctrl+N 新增一個檔案，然後貼上你整理好的 Markdown 內容，接著按下 Ctrl+A 全選所有文字
按下 Ctrl+Shift+P 或 F1 開啟 VS Code 命令清單，輸入 Escape JSON String 並按下 Enter 就會把你的 Markdown 內容轉換成 JSON 字串格式
開啟你的 settings.json 設定檔，鍵盤游標移動到要貼上的位置，然後按下 Ctrl+V 貼上剛剛轉換好的 JSON 字串

這樣就完成了！ 👍

以下是我的最終成果：

"github.copilot.chat.commitMessageGeneration.instructions": [
  {
    "text": "# Conventional Commits 1.0.0\r\n\r\n## Summary\r\n\r\nThe Conventional Commits specification is a lightweight convention on top of commit messages. It provides an easy set of rules for creating an explicit commit history; which makes it easier to write automated tools on top of. This convention dovetails with [SemVer](http://semver.org/), by describing the features, fixes, and breaking changes made in commit messages.\r\n\r\nThe commit message should be structured as follows:\r\n\r\n* * * * *\r\n\r\n```\r\n<type>[optional scope]: <description>\r\n\r\n[optional body]\r\n\r\n[optional footer(s)]\r\n```\r\n\r\n* * * * *\r\n\r\nThe commit contains the following structural elements, to communicate intent to the consumers of your library:\r\n\r\n1. **fix:** a commit of the *type* `fix` patches a bug in your codebase (this correlates with [`PATCH`](http://semver.org/#summary) in Semantic Versioning).\r\n2. **feat:** a commit of the *type* `feat` introduces a new feature to the codebase (this correlates with [`MINOR`](http://semver.org/#summary) in Semantic Versioning).\r\n3. **BREAKING CHANGE:** a commit that has a footer `BREAKING CHANGE:`, or appends a `!` after the type/scope, introduces a breaking API change (correlating with [`MAJOR`](http://semver.org/#summary) in Semantic Versioning). A BREAKING CHANGE can be part of commits of any *type*.\r\n4. *types* other than `fix:` and `feat:` are allowed, for example [@commitlint/config-conventional](https://github.com/conventional-changelog/commitlint/tree/master/%40commitlint/config-conventional) (based on the [Angular convention](https://github.com/angular/angular/blob/22b96b9/CONTRIBUTING.md#-commit-message-guidelines)) recommends `build:`, `chore:`, `ci:`, `docs:`, `style:`, `refactor:`, `perf:`, `test:`, and others.\r\n5. *footers* other than `BREAKING CHANGE: <description>` may be provided and follow a convention similar to [git trailer format](https://git-scm.com/docs/git-interpret-trailers).\r\n\r\nAdditional types are not mandated by the Conventional Commits specification, and have no implicit effect in Semantic Versioning (unless they include a BREAKING CHANGE). A scope may be provided to a commit's type, to provide additional contextual information and is contained within parenthesis, e.g., `feat(parser): add ability to parse arrays`.\r\n\r\n## Examples\r\n\r\n### Commit message with description and breaking change footer\r\n\r\n```\r\nfeat: allow provided config object to extend other configs\r\n\r\nBREAKING CHANGE: `extends` key in config file is now used for extending other config files\r\n```\r\n\r\n### Commit message with `!` to draw attention to breaking change\r\n\r\n```\r\nfeat!: send an email to the customer when a product is shipped\r\n```\r\n\r\n### Commit message with scope and `!` to draw attention to breaking change\r\n\r\n```\r\nfeat(api)!: send an email to the customer when a product is shipped\r\n```\r\n\r\n### Commit message with both `!` and BREAKING CHANGE footer\r\n\r\n```\r\nchore!: drop support for Node 6\r\n\r\nBREAKING CHANGE: use JavaScript features not available in Node 6.\r\n```\r\n\r\n### Commit message with no body\r\n\r\n```\r\ndocs: correct spelling of CHANGELOG\r\n```\r\n\r\n### Commit message with scope\r\n\r\n```\r\nfeat(lang): add Polish language\r\n```\r\n\r\n### Commit message with multi-paragraph body and multiple footers\r\n\r\n```\r\nfix: prevent racing of requests\r\n\r\nIntroduce a request id and a reference to latest request. Dismiss\r\nincoming responses other than from latest request.\r\n\r\nRemove timeouts which were used to mitigate the racing issue but are\r\nobsolete now.\r\n\r\nReviewed-by: Z\r\nRefs: #123\r\n```\r\n\r\n## Specification\r\n\r\nThe key words \"MUST\", \"MUST NOT\", \"REQUIRED\", \"SHALL\", \"SHALL NOT\", \"SHOULD\", \"SHOULD NOT\", \"RECOMMENDED\", \"MAY\", and \"OPTIONAL\" in this document are to be interpreted as described in [RFC 2119](https://www.ietf.org/rfc/rfc2119.txt).\r\n\r\n1. Commits MUST be prefixed with a type, which consists of a noun, `feat`, `fix`, etc., followed by the OPTIONAL scope, OPTIONAL `!`, and REQUIRED terminal colon and space.\r\n2. The type `feat` MUST be used when a commit adds a new feature to your application or library.\r\n3. The type `fix` MUST be used when a commit represents a bug fix for your application.\r\n4. A scope MAY be provided after a type. A scope MUST consist of a noun describing a section of the codebase surrounded by parenthesis, e.g., `fix(parser):`\r\n5. A description MUST immediately follow the colon and space after the type/scope prefix. The description is a short summary of the code changes, e.g., *fix: array parsing issue when multiple spaces were contained in string*.\r\n6. A longer commit body MAY be provided after the short description, providing additional contextual information about the code changes. The body MUST begin one blank line after the description.\r\n7. A commit body is free-form and MAY consist of any number of newline separated paragraphs.\r\n8. One or more footers MAY be provided one blank line after the body. Each footer MUST consist of a word token, followed by either a `:<space>` or `<space>#` separator, followed by a string value (this is inspired by the [git trailer convention](https://git-scm.com/docs/git-interpret-trailers)).\r\n9. A footer's token MUST use `-` in place of whitespace characters, e.g., `Acked-by` (this helps differentiate the footer section from a multi-paragraph body). An exception is made for `BREAKING CHANGE`, which MAY also be used as a token.\r\n10. A footer's value MAY contain spaces and newlines, and parsing MUST terminate when the next valid footer token/separator pair is observed.\r\n11. Breaking changes MUST be indicated in the type/scope prefix of a commit, or as an entry in the footer.\r\n12. If included as a footer, a breaking change MUST consist of the uppercase text BREAKING CHANGE, followed by a colon, space, and description, e.g., *BREAKING CHANGE: environment variables now take precedence over config files*.\r\n13. If included in the type/scope prefix, breaking changes MUST be indicated by a `!` immediately before the `:`. If `!` is used, `BREAKING CHANGE:` MAY be omitted from the footer section, and the commit description SHALL be used to describe the breaking change.\r\n14. Types other than `feat` and `fix` MAY be used in your commit messages, e.g., *docs: update ref docs.*\r\n15. The units of information that make up Conventional Commits MUST NOT be treated as case sensitive by implementors, with the exception of BREAKING CHANGE which MUST be uppercase.\r\n16. BREAKING-CHANGE MUST be synonymous with BREAKING CHANGE, when used as a token in a footer.\r\n\r\n## Why Use Conventional Commits\r\n\r\n- Automatically generating CHANGELOGs.\r\n- Automatically determining a semantic version bump (based on the types of commits landed).\r\n- Communicating the nature of changes to teammates, the public, and other stakeholders.\r\n- Triggering build and publish processes.\r\n- Making it easier for people to contribute to your projects, by allowing them to explore a more structured commit history.\r\n\r\n## FAQ\r\n\r\n### How should I deal with commit messages in the initial development phase?\r\n\r\nWe recommend that you proceed as if you've already released the product. Typically *somebody*, even if it's your fellow software developers, is using your software. They'll want to know what's fixed, what breaks etc.\r\n\r\n### Are the types in the commit title uppercase or lowercase?\r\n\r\nAny casing may be used, but it's best to be consistent.\r\n\r\n### What do I do if the commit conforms to more than one of the commit types?\r\n\r\nGo back and make multiple commits whenever possible. Part of the benefit of Conventional Commits is its ability to drive us to make more organized commits and PRs.\r\n\r\n### Doesn't this discourage rapid development and fast iteration?\r\n\r\nIt discourages moving fast in a disorganized way. It helps you be able to move fast long term across multiple projects with varied contributors.\r\n\r\n### Might Conventional Commits lead developers to limit the type of commits they make because they'll be thinking in the types provided?\r\n\r\nConventional Commits encourages us to make more of certain types of commits such as fixes. Other than that, the flexibility of Conventional Commits allows your team to come up with their own types and change those types over time.\r\n\r\n### How does this relate to SemVer?\r\n\r\n`fix` type commits should be translated to `PATCH` releases. `feat` type commits should be translated to `MINOR` releases. Commits with `BREAKING CHANGE` in the commits, regardless of type, should be translated to `MAJOR` releases.\r\n\r\n### How should I version my extensions to the Conventional Commits Specification, e.g. `@jameswomack/conventional-commit-spec`?\r\n\r\nWe recommend using SemVer to release your own extensions to this specification (and encourage you to make these extensions!)\r\n\r\n### What do I do if I accidentally use the wrong commit type?\r\n\r\n#### When you used a type that's of the spec but not the correct type, e.g. `fix` instead of `feat`\r\n\r\nPrior to merging or releasing the mistake, we recommend using `git rebase -i` to edit the commit history. After release, the cleanup will be different according to what tools and processes you use.\r\n\r\n#### When you used a type *not* of the spec, e.g. `feet` instead of `feat`\r\n\r\nIn a worst case scenario, it's not the end of the world if a commit lands that does not meet the Conventional Commits specification. It simply means that commit will be missed by tools that are based on the spec.\r\n\r\n### Do all my contributors need to use the Conventional Commits specification?\r\n\r\nNo! If you use a squash based workflow on Git lead maintainers can clean up the commit messages as they're merged---adding no workload to casual committers. A common workflow for this is to have your git system automatically squash commits from a pull request and present a form for the lead maintainer to enter the proper git commit message for the merge.\r\n\r\n### How does Conventional Commits handle revert commits?\r\n\r\nReverting code can be complicated: are you reverting multiple commits? if you revert a feature, should the next release instead be a patch?\r\n\r\nConventional Commits does not make an explicit effort to define revert behavior. Instead we leave it to tooling authors to use the flexibility of *types* and *footers* to develop their logic for handling reverts.\r\n\r\nOne recommendation is to use the `revert` type, and a footer that references the commit SHAs that are being reverted:\r\n\r\n```\r\nrevert: let us never again speak of the noodle incident\r\n\r\nRefs: 676104e, a215868\r\n```"
  },
  {
    "text": "請一律使用正體中文來撰寫記錄"
  }
],

除此之外，你其實還可以用指定檔案路徑的方式來設定這個自訂指令，這樣你就可以在不同的專案中套用不同的提交訊息風格，這樣更加方便團隊使用一致的風格來管理 Commit Log 格式。

"github.copilot.chat.commitMessageGeneration.instructions": [
  {
    "file": ".copilot-commit-message-instructions.md"
  },
  {
    "text": "請一律使用正體中文來撰寫記錄"
  }
],

注意: 上述範例主要是要求你在 VS Code 工作區的根目錄下建立一個 .copilot-commit-message-instructions.md 檔案，記得加入版控。

3. 學會如何使用自訂指令寫 Git 提交訊息

當你完成了上述的設定之後，接下來你就可以在 VS Code 中使用 GitHub Copilot 來幫你撰寫 Git 提交訊息了！當你在「原始檔控制」窗格提交程式碼時，你會看到有個 Copilot 專用的 Icon 圖示 (如下圖示)，按下去就會自動產生一個提交訊息的建議，如果有需要你還可以微調一下，就可以按下「提交」建立版本了！👍

VS Code 原始檔控制 > 使用 Copilot 產生認可訊息