fix: deep merge in source and toml config (#220)

* fix: deep merge in source and toml config

node/declaration.test.ts

@@ -0,0 +1,72 @@
+import { test, expect } from 'vitest'
+
+import { FunctionConfig } from './config.js'
+import { getDeclarationsFromConfig } from './declaration.js'
+
+test('In source config takes precedence over netlify.toml config', () => {
+  const tomlConfig = [
+    { function: 'geolocation', path: '/geo', cache: 'off' },
+    { function: 'json', path: '/json', cache: 'manual' },
+  ]
+
+  const funcConfig = {
+    geolocation: { path: '/geo-isc', cache: 'manual' },
+    json: { path: '/json', cache: 'off' },
+  } as Record<string, FunctionConfig>
+
+  const expectedDeclarations = [
+    { function: 'geolocation', path: '/geo-isc', cache: 'manual' },
+    { function: 'json', path: '/json', cache: 'off' },
+  ]
+
+  const declarations = getDeclarationsFromConfig(tomlConfig, funcConfig)
+
+  expect(declarations).toEqual(expectedDeclarations)
+})
+
+test("Declarations don't break if no in source config is provided", () => {
+  const tomlConfig = [
+    { function: 'geolocation', path: '/geo', cache: 'off' },
+    { function: 'json', path: '/json', cache: 'manual' },
+  ]
+
+  const funcConfig = {
+    geolocation: { path: '/geo-isc', cache: 'manual' },
+    json: {},
+  } as Record<string, FunctionConfig>
+
+  const expectedDeclarations = [
+    { function: 'geolocation', path: '/geo-isc', cache: 'manual' },
+    { function: 'json', path: '/json', cache: 'manual' },
+  ]
+
+  const declarations = getDeclarationsFromConfig(tomlConfig, funcConfig)
+
+  expect(declarations).toEqual(expectedDeclarations)
+})
+
+test('In source config works independent of the netlify.toml file if a path is defined and otherwise if no path is set', () => {
+  const tomlConfig = [{ function: 'geolocation', path: '/geo', cache: 'off' }]
+
+  const funcConfigWithPath = {
+    json: { path: '/json', cache: 'off' },
+  } as Record<string, FunctionConfig>
+
+  const funcConfigWithoutPath = {
+    json: { cache: 'off' },
+  } as Record<string, FunctionConfig>
+
+  const expectedDeclarationsWithISCPath = [
+    { function: 'geolocation', path: '/geo', cache: 'off' },
+    { function: 'json', path: '/json', cache: 'off' },
+  ]
+
+  const expectedDeclarationsWithoutISCPath = [{ function: 'geolocation', path: '/geo', cache: 'off' }]
+
+  const declarationsWithISCPath = getDeclarationsFromConfig(tomlConfig, funcConfigWithPath)
+
+  const declarationsWithoutISCPath = getDeclarationsFromConfig(tomlConfig, funcConfigWithoutPath)
+
+  expect(declarationsWithISCPath).toEqual(expectedDeclarationsWithISCPath)
+  expect(declarationsWithoutISCPath).toEqual(expectedDeclarationsWithoutISCPath)
+})

node/declaration.ts

@@ -25,17 +25,14 @@ export const getDeclarationsFromConfig = (
 
   // We start by iterating over all the TOML declarations. For any declaration
   // for which we also have a function configuration object, we replace the
-  // path because that object takes precedence.
+  // defined config (currently path or cache or both) because that object takes
+  // precedence.
   for (const declaration of tomlDeclarations) {
-    const { path } = functionsConfig[declaration.function] ?? {}
+    const config = functionsConfig[declaration.function] ?? {}
 
-    if (path) {
-      functionsVisited.add(declaration.function)
+    functionsVisited.add(declaration.function)
 
-      declarations.push({ ...declaration, path })
-    } else {
-      declarations.push(declaration)
-    }
+    declarations.push({ ...declaration, ...config })
   }
 
   // Finally, we must create declarations for functions that are not declared