Add validation to parseVariables (substitute) (#1750)

substitute/src/run.ts

@@ -2,19 +2,23 @@ import { promises as fs } from 'fs'
 import * as core from '@actions/core'
 import * as glob from '@actions/glob'
 
-interface Inputs {
+type Inputs = {
   files: string
   variables: Map<string, string>
 }
 
 export const parseVariables = (variables: string[]): Map<string, string> => {
-  const m = new Map<string, string>()
+  const map = new Map<string, string>()
   for (const s of variables) {
-    const k = s.substring(0, s.indexOf('='))
-    const v = s.substring(s.indexOf('=') + 1)
-    m.set(k, v)
+    const equalIndex = s.indexOf('=')
+    if (equalIndex === -1) {
+      throw new Error(`variable must be in the form of key=value: ${s}`)
+    }
+    const k = s.substring(0, equalIndex)
+    const v = s.substring(equalIndex + 1)
+    map.set(k, v)
   }
-  return m
+  return map
 }
 
 export const run = async (inputs: Inputs): Promise<void> => {

substitute/tests/run.test.ts

@@ -1,7 +1,7 @@
 import * as os from 'os'
 import { promises as fs } from 'fs'
 import * as path from 'path'
-import { run } from '../src/run.js'
+import { parseVariables, run } from '../src/run.js'
 
 test('variables are replaced', async () => {
   const workspace = await fs.mkdtemp(path.join(os.tmpdir(), 'substitute-action-'))
@@ -27,3 +27,21 @@ image: 123456789012.dkr.ecr.ap-northeast-1.amazonaws.com/example:latest
 })
 
 const readContent = async (f: string): Promise<string> => (await fs.readFile(f)).toString()
+
+describe('parseVariables', () => {
+  it('parses variables', () => {
+    expect(parseVariables(['DOCKER_IMAGE=123', 'NAMESPACE=develop', 'VERSION='])).toStrictEqual(
+      new Map([
+        ['DOCKER_IMAGE', '123'],
+        ['NAMESPACE', 'develop'],
+        ['VERSION', ''],
+      ]),
+    )
+  })
+
+  it('throws an error if variable is not in the form of key=value', () => {
+    expect(() => parseVariables(['DOCKER_IMAGE=123', 'NAMESPACE'])).toThrow(
+      'variable must be in the form of key=value: NAMESPACE',
+    )
+  })
+})