test: add failing test for TypeScript reserved keyword scalar names

Add tests that demonstrate the issue where scalar names that are TypeScript
reserved keywords (like 'bigint', 'boolean') generate invalid TypeScript code.
The fix is commented out with TODO markers.

Issue #1354

Author: jasonkuhrt

src/generator/generators/Scalar.test.ts

@@ -0,0 +1,74 @@
+import * as MemFS from 'memfs'
+import { describe, expect, test } from 'vitest'
+import { generate } from '../generator/generate.js'
+
+const fs = MemFS.fs.promises as any
+
+describe('Scalar module generation', () => {
+  describe('Issue #1354 - TypeScript reserved keywords', () => {
+    test('should escape reserved TypeScript keywords in scalar names', async () => {
+      await generate({
+        fs,
+        schema: {
+          type: 'sdl',
+          sdl: `
+            scalar bigint
+            scalar boolean
+            
+            type Query {
+              getBigint: bigint
+              getBoolean: boolean
+            }
+          `
+        }
+      })
+      
+      const scalarModule = MemFS.fs.readFileSync('./graffle/modules/scalar.ts', 'utf8')
+      
+      // The generated code should use escaped names (e.g., $bigint instead of bigint)
+      // to avoid TypeScript compilation errors
+      expect(scalarModule).toContain('export type $bigint =')
+      expect(scalarModule).toContain('export type $boolean =')
+      
+      // But the scalar references should still use the original names
+      expect(scalarModule).toContain('ScalarCodecless<"bigint">')
+      expect(scalarModule).toContain('ScalarCodecless<"boolean">')
+    })
+
+    test('should escape reserved keywords for custom scalars with codecs', async () => {
+      // First create the custom scalars file
+      await fs.mkdir('./custom-scalars', { recursive: true })
+      await fs.writeFile('./custom-scalars/scalars.js', `
+        export const bigint = {
+          encode: (value) => value.toString(),
+          decode: (value) => BigInt(value),
+        }
+      `)
+      
+      await generate({
+        fs,
+        schema: {
+          type: 'sdl',
+          sdl: `
+            scalar bigint
+            type Query {
+              getBigint: bigint
+            }
+          `
+        },
+        customScalars: './custom-scalars/scalars.js'
+      })
+      
+      const scalarModule = MemFS.fs.readFileSync('./graffle/modules/scalar.ts', 'utf8')
+      
+      // Type definitions should be escaped
+      expect(scalarModule).toContain('export type $bigint = typeof')
+      expect(scalarModule).toContain('type $bigint_ = typeof')
+      expect(scalarModule).toContain('export type $bigintDecoded =')
+      expect(scalarModule).toContain('export type $bigintEncoded =')
+      
+      // But runtime references should use original names
+      expect(scalarModule).toContain('typeof CustomScalars.bigint')
+    })
+  })
+})

src/generator/generators/Scalar.ts

@@ -3,7 +3,9 @@ import { Grafaid } from '../../lib/grafaid/_namespace.js'
 import { Tex } from '../../lib/tex/_namespace.js'
 import { $ } from '../helpers/identifiers.js'
 import { createModuleGenerator } from '../helpers/moduleGenerator.js'
-import { renderName, typeTitle2 } from '../helpers/render.js'
+import { typeTitle2 } from '../helpers/render.js'
+// TODO: Uncomment to fix issue #1354
+// import { renderName, typeTitle2 } from '../helpers/render.js'
 
 export const ModuleGeneratorScalar = createModuleGenerator(
   `scalar`,
@@ -32,12 +34,13 @@ export const ModuleGeneratorScalar = createModuleGenerator(
         code(typeTitle2(`custom scalar type`)(scalar))
         code``
         code`
-          export type ${renderName(scalar.name)} = typeof ${$.CustomScalars}.${scalar.name}
+          // TODO: Fix issue #1354 - use renderName() here
+          export type ${scalar.name} = typeof ${$.CustomScalars}.${scalar.name}
           // Without this we get error:
           // "Exported type alias 'DateDecoded' has or is using private name 'Date'."
-          type ${renderName(scalar.name)}_ = typeof ${$.CustomScalars}.${scalar.name}
-          export type ${renderName(scalar.name)}Decoded = ${$.$$Utilities}.Schema.Scalar.GetDecoded<${renderName(scalar.name)}_>
-          export type ${renderName(scalar.name)}Encoded = ${$.$$Utilities}.Schema.Scalar.GetEncoded<${renderName(scalar.name)}_>
+          type ${scalar.name}_ = typeof ${$.CustomScalars}.${scalar.name}
+          export type ${scalar.name}Decoded = ${$.$$Utilities}.Schema.Scalar.GetDecoded<${scalar.name}_>
+          export type ${scalar.name}Encoded = ${$.$$Utilities}.Schema.Scalar.GetEncoded<${scalar.name}_>
         `
         code``
       }
@@ -56,7 +59,8 @@ export const ModuleGeneratorScalar = createModuleGenerator(
       for (const scalar of config.schema.kindMap.list.ScalarCustom) {
         code(typeTitle2(`custom scalar type`)(scalar))
         code``
-        code`export type ${renderName(scalar.name)} = ${$.$$Utilities}.Schema.Scalar.ScalarCodecless<'${scalar.name}'>`
+        // TODO: Fix issue #1354 - use renderName() here
+        code`export type ${scalar.name} = ${$.$$Utilities}.Schema.Scalar.ScalarCodecless<'${scalar.name}'>`
         // code(`import type { String as ${scalar.name} } from '${config.paths.imports.grafflePackage.scalars}'`)
         // code()
         // code(`export { String as ${scalar.name} } from '${config.paths.imports.grafflePackage.scalars}'`)