is-affected

Build optimisation tool to run commands on feature branches only if they affect files matching a given glob.

!Cloud Build

CLI

``shell
Usage: is-affected [options]

runs command only if the git diff since the fork point from master branch contains files matching glob

Options:
-V, --version output the version number
--pattern [pattern...] provide one or more patterns to check file paths from git diff against
--repo git directory (default: "./")
--cmd the command to be run if diff matches glob
--cwd working directory to be used to run command
--main name of the main branch of your repo, used when no --since is provided to find the merge base commit (default: "origin/master")
--since commit to diff with
-h, --help display help for command
`

Example

To run npm run build only if the git diff between your current branch head and the base commit on the master branch contains files matching glob app/client/**.

`shell
npx is-affected app/client/** --cmd "npm run build" --cwd "app/client"
`

Javascript API

`javascript
const { isAffected, exec } = require("is-affected");

const build = async () => {
const shouldBuild = await isAffected(
"app/client/**",
);

if (shouldBuild) {
await exec("npm run build", "app/client");
}
};

build();
`

or with options object (using defaults here):
`javascript
const shouldBuild = await isAffected(
"app/client/**", // see match patterns below
{
repo: "./",
cmd: "npm run build",
cwd: process.cwd(),
mainBranch: "origin/master",
since: undefined,
},
);
`

Match patterns

A match means that the git diff contains paths that match the pattern and your code is 'affected'.

$3


You can use a negated pattern: !src/scripts

This will ignore changes in the src/scripts folder. If your diff contains only changes in src/scripts then your code will not be marked as 'affected'.

$3

A normal pattern (aka non negated) will add paths to the match list. Negated patterns will remove paths from the list. Your code is 'affected' when the list is not empty after the last pattern has been evaluated.

`javascript
const shouldBuild = await isAffected([
'src/**',
'!src/tests/**',
]);
`

or using cli:
`
npx is-affected src/ !src/tests/
`

Note that if your shell is automatically expanding glob patterns you should escape the asterix:

`
npx is-affected src/\ !src/tests/\
`

The above example will monitor all paths in the src folder except for those in the tests` subfolder.