feat: add build.edge_functions_import_map config property (#4774)

* feat: add `functions.import_map` config property

* refactor: rename property

* refactor: update validation example

Author: eduardoboucas

packages/config/src/validate/validations.js

@@ -187,6 +187,14 @@ export const POST_NORMALIZE_VALIDATIONS = [
     message: 'must be a string.',
     example: () => ({ build: { edge_functions: 'edge-functions' } }),
   },
+  {
+    property: 'build.edge_functions_import_map',
+    check: isString,
+    message: 'must be a string.',
+    example: () => ({
+      build: { edge_functions_import_map: 'path/to/import_map.json' },
+    }),
+  },
   {
     property: 'functions.*',
     check: isPlainObj,

packages/config/tests/validate/fixtures/build_edge_functions_import_map/netlify.toml

@@ -0,0 +1,2 @@
+[build]
+edge_functions_import_map = ["not", "a", "string"]

packages/config/tests/validate/snapshots/tests.js.md

@@ -476,6 +476,27 @@ Generated by [AVA](https://avajs.dev).
     `When resolving config file packages/config/tests/validate/fixtures/build_edge_functions_parent/netlify.toml:␊
     Configuration property "build.edge_functions" "edge_functions_dir" must be inside the repository root directory.`
 
+## build.edge_functions_import_map: string
+
+> Snapshot 1
+
+    `When resolving config file packages/config/tests/validate/fixtures/build_edge_functions_import_map/netlify.toml:␊
+    Configuration property build.edge_functions_import_map must be a string.␊
+    ␊
+    Invalid syntax␊
+    ␊
+      [build]␊
+      edge_functions_import_map = [␊
+        "not",␊
+        "a",␊
+        "string"␊
+      ]␊
+    ␊
+    Valid syntax␊
+    ␊
+      [build]␊
+      edge_functions_import_map = "path/to/import_map.json"`
+
 ## build.base: string
 
 > Snapshot 1

packages/config/tests/validate/snapshots/tests.js.snap

@@ -113,6 +113,11 @@ test('build.edge_functions: parent directory', async (t) => {
   t.snapshot(normalizeOutput(output))
 })
 
+test('build.edge_functions_import_map: string', async (t) => {
+  const output = await new Fixture('./fixtures/build_edge_functions_import_map').runWithConfig()
+  t.snapshot(normalizeOutput(output))
+})
+
 test('build.base: string', async (t) => {
   const output = await new Fixture('./fixtures/build_base_string').runWithConfig()
   t.snapshot(normalizeOutput(output))