Add is-pr command (#29)

README.md

@@ -100,6 +100,25 @@ You can perform the automated bump in the merge build by using:
   bumpr bump
   ```
 
+If you have some other CI script you want to run only in a PR build, you can check by using
+
+  ```
+  bumpr is-pr
+  ```
+
+This command will exit with a 0 exit code if the current build is a PR build, and a 1 if it is not. So you can have
+a CI script like this:
+
+  ```
+  bumpr is-pr && echo "Do PR stuff"
+  ```
+
+or
+
+  ```
+  bumpr is-pr || echo "Do merge stuff"
+  ```
+
 If you have the `logging` feature enabled, you can output a specific key from the log file using:
 
   ```

bin/cli.js

@@ -35,6 +35,17 @@ program
     withBumpr(bumpr => bumpr.bump())
   })
 
+program
+  .command('is-pr')
+  .description('check if current build is a PR build')
+  .action(() => {
+    // Use exit code 0 if the current build is a PR build, 1 if it is not
+    // this will allow CI scripts to do things like:
+    // $ bumpr is-pr && echo "A PR build"
+    // $ bumpr is-pr || echo "A merge build"
+    withBumpr(bumpr => process.exit(bumpr.isPr() ? 0 : 1))
+  })
+
 program
   .command('log <key>')
   .description(`Output the given key from the ${name} log file`)

src/bumpr.js

@@ -103,6 +103,13 @@ class Bumpr {
     })
   }
 
+  /**
+   * Check if a build is happening in a PR
+   */
+  isPr() {
+    return this.config.computed.ci.isPr
+  }
+
   /**
    * Read the bumpr log and output the given key from it
    * @returns {Promise} a promise resolved with the value or rejected on error

src/tests/bumpr.test.js

@@ -278,6 +278,31 @@ describe('Bumpr', () => {
     })
   })
 
+  describe('.isPr()', () => {
+    let ret
+    describe('when not a PR build', () => {
+      beforeEach(() => {
+        set(bumpr.config, 'computed.ci.isPr', false)
+        ret = bumpr.isPr()
+      })
+
+      it('should return false', () => {
+        expect(ret).toEqual(false)
+      })
+    })
+
+    describe('when it is a PR build', () => {
+      beforeEach(() => {
+        set(bumpr.config, 'computed.ci.isPr', true)
+        ret = bumpr.isPr()
+      })
+
+      it('should return true', () => {
+        expect(ret).toEqual(true)
+      })
+    })
+  })
+
   describe('.log()', () => {
     beforeEach(() => {
       set(bumpr.config, 'features.logging.file', 'the-log-file')