suggester: treat null and undefined as the same in eq check

src/lib/eq/eq.test.ts

@@ -0,0 +1,14 @@
+import {eq} from './eq'
+
+describe('EQ', () => {
+  test('EQ', () => {
+    expect(eq(undefined, undefined)).toBeTruthy()
+    expect(eq(undefined, null)).toBeTruthy()
+    expect(eq(null, undefined)).toBeTruthy()
+    expect(eq(null, null)).toBeTruthy()
+    expect(eq(1, 1)).toBeTruthy()
+    expect(eq(1, 2)).toBeFalsy()
+    expect(eq(2, 1)).toBeFalsy()
+    expect(eq(1, '1')).toBeFalsy()
+  })
+})

src/lib/eq/eq.ts

@@ -0,0 +1,13 @@
+// eq is an equality check, but treats null and undefined as equal
+export const eq = (
+  a: number | undefined | null | string,
+  b: number | undefined | null | string
+): boolean => {
+  if (a === null) {
+    a = undefined
+  }
+  if (b === null) {
+    b = undefined
+  }
+  return a === b
+}

src/lib/eq/index.ts

@@ -0,0 +1 @@
+export * from './eq'

src/lib/index.ts

@@ -4,3 +4,4 @@ export * from './octokit'
 export * from './track'
 export * from './github'
 export * from './features'
+export * from './eq'

src/suggester/main.ts

@@ -4,7 +4,7 @@ import {RequestError} from '@octokit/request-error'
 import {track} from '../lib/track'
 import {suggest} from '../lib/github'
 import {get} from '../lib/jobs'
-import {Octokit, required} from '../lib'
+import {Octokit, required, eq} from '../lib'
 import {ForbiddenError} from '../lib/api'
 
 const jobID = required('codeball-job-id')
@@ -94,7 +94,7 @@ const suggestViaGitHub = async ({
   pull_number: number
 }) =>
   get(jobID).then(async job => {
-    let suggestions = job?.comment?.suggestions
+    const suggestions = job?.comment?.suggestions
     if (!suggestions) return
     if (suggestions.length === 0) return
 
@@ -143,11 +143,10 @@ const suggestViaGitHub = async ({
       }
 
       const alreadyExists = existingComments.some(comment => {
-        const isSameBody = comment.body === request.body
-        // NOTE: == is intentional, we want to treat undefined and null as equal
-        const isSameStartLine = comment.start_line == request.start_line
-        const isSameEndLine = comment.line === request.line
-        const isSame = isSameBody && isSameStartLine && isSameEndLine
+        const isSameBody = eq(comment.body, request.body)
+        const isSameStartLineLine = eq(comment.start_line, request.start_line)
+        const isSameEndLine = eq(comment.line, request.line)
+        const isSame = isSameBody && isSameStartLineLine && isSameEndLine
         return isSame
       })