fix(workflows): avoid repeated reference overlap scans

Author: waleedlatif1

apps/sim/lib/workflows/editing/code-syntax.test.ts

@@ -79,6 +79,16 @@ describe('embedded Function syntax checks', () => {
     expect(report.issues[0].message).toContain('more than 10000 variable placeholders')
   })
 
+  it('checks reference-dense code within the supported body budget without repeated overlap scans', async () => {
+    const code = `/*${'<a.b>'.repeat(200_000)}*/return 1`
+    const started = performance.now()
+    const report = await collectWorkflowCodeSyntax({ renderer: block(code) })
+
+    expect(report.issues).toEqual([])
+    expect(report.check.detail).toContain('1 used placeholder values')
+    expect(performance.now() - started).toBeLessThan(2_000)
+  }, 60_000)
+
   it('never evaluates side effects while checking code', async () => {
     const key = '__workflowLintExecuted'
     await collectWorkflowCodeSyntax({

packages/utils/src/workflow-references.test.ts

@@ -52,6 +52,22 @@ describe('workflow references', () => {
     ])
   })
 
+  it.each([
+    [
+      '<before.x>{{<hidden.x><alsoHidden.y>}}<after.y>',
+      ['<before.x>', '{{<hidden.x><alsoHidden.y>}}', '<after.y>'],
+    ],
+    ['<before.x><{{ENV}}.value><after.y>', ['<before.x>', '{{ENV}}', '<after.y>']],
+    ['{{ONE}}{{TWO}}<after.y>', ['{{ONE}}', '{{TWO}}', '<after.y>']],
+    ['{{outer{{<hidden.x>}}}}<after.y>', ['{{<hidden.x>}}', '<after.y>']],
+    ['{{<first.x>\n<second.y>}}', ['<first.x>', '<second.y>']],
+    ['<broken\n{{ENV}}<= <after.y>', ['{{ENV}}', '<after.y>']],
+  ])('preserves environment overlap precedence and reference offsets in %s', (source, expected) => {
+    const tokens = findWorkflowReferenceTokens(source)
+    expect(tokens.map((token) => token.value)).toEqual(expected)
+    for (const token of tokens) expect(source.slice(token.start, token.end)).toBe(token.value)
+  })
+
   it('scans long runs of opening brackets while preserving final reference offsets', () => {
     expect(findWorkflowReferenceTokens(`${'<'.repeat(10_000)}value>`)).toEqual([
       {

packages/utils/src/workflow-references.ts

@@ -66,6 +66,8 @@ export function findWorkflowReferenceTokens(source: string): WorkflowReferenceTo
     tokens.push({ kind: 'environment', value: match[0], start, end: start + match[0].length })
   }
 
+  const environmentCount = tokens.length
+  let environmentIndex = 0
   let candidateStart = -1
   for (let index = 0; index < source.length; index += 1) {
     const character = source[index]
@@ -84,7 +86,11 @@ export function findWorkflowReferenceTokens(source: string): WorkflowReferenceTo
     if (split && isLikelyWorkflowReferenceSegment(candidate)) {
       const start = candidateStart + split.leading.length
       const end = start + split.reference.length
-      if (!tokens.some((token) => start < token.end && end > token.start)) {
+      /** Both scans advance in source order; prior workflow candidates cannot overlap. */
+      while (environmentIndex < environmentCount && tokens[environmentIndex].end <= start) {
+        environmentIndex++
+      }
+      if (environmentIndex === environmentCount || end <= tokens[environmentIndex].start) {
         tokens.push({ kind: 'workflow', value: split.reference, start, end })
       }
     }