Add imports to the summary produced by the server

This only includes the imports from the first fragment. We'll eventually
need to decide what to do about imports in part files, preferably before
that feature has shipped, but the lack of support won't impact users
today.

Change-Id: Ia38149f619dc22085ed02a90892e0af13eb188dd
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/443143
Reviewed-by: Jake Macdonald <[email protected]>
Commit-Queue: Brian Wilkerson <[email protected]>

Author: bwilkerson

pkg/analysis_server/lib/src/lsp/handlers/custom/handler_summary.dart

@@ -70,6 +70,14 @@ class SummaryWriter {
 
   String summarize() {
     var libraryElement = result.element;
+
+    // Write a summary of the imports.
+    var libraryImports = libraryElement.firstFragment.libraryImports;
+    for (var libraryImport in libraryImports) {
+      summarizeImport(libraryImport);
+    }
+
+    // Write a summary of the declarations in the export namespace.
     var definedNames = libraryElement.exportNamespace.definedNames2;
     var needsSeparator = false;
     for (var element in definedNames.values) {
@@ -351,6 +359,35 @@ class SummaryWriter {
     buffer.write(' ');
   }
 
+  void summarizeImport(LibraryImport libraryImport) {
+    if (libraryImport.isSynthetic) return;
+    buffer.write("import '");
+    buffer.write(libraryImport.uri.uriString);
+    buffer.write("'");
+    if (libraryImport.prefix?.name case var prefix?) {
+      buffer.write(' as ');
+      buffer.write(prefix);
+    }
+    for (var combinator in libraryImport.combinators) {
+      if (combinator is ShowElementCombinator) {
+        var prefix = ' show ';
+        for (var name in combinator.shownNames) {
+          buffer.write(prefix);
+          buffer.write(name);
+          prefix = ', ';
+        }
+      } else if (combinator is HideElementCombinator) {
+        var prefix = ' hide ';
+        for (var name in combinator.hiddenNames) {
+          buffer.write(prefix);
+          buffer.write(name);
+          prefix = ', ';
+        }
+      }
+    }
+    buffer.writeln(';');
+  }
+
   void summarizeList<E>(List<E> list, void Function(E) summarizeElement) {
     var separator = '';
     for (var element in list) {
@@ -497,3 +534,13 @@ class SummaryWriter {
     summarizeTypes(types);
   }
 }
+
+extension on DirectiveUri {
+  String get uriString => switch (this) {
+    DirectiveUriWithLibrary(:var source) => source.uri.toString(),
+    DirectiveUriWithRelativeUriString(:var relativeUriString) =>
+      relativeUriString,
+    DirectiveUri() =>
+      throw UnimplementedError('Unhandled instance of type $runtimeType'),
+  };
+}

pkg/analysis_server/test/lsp/summary_test.dart

@@ -132,6 +132,22 @@ extension type E(int self) {
     );
   }
 
+  Future<void> test_imports() async {
+    failTestOnErrorDiagnostic = false;
+    await verifySummary(
+      '''
+import 'dart:async' show Stream;
+import 'package:test/test.dart' as test;
+import 'other.dart' deferred as o hide SomeClass;
+''',
+      '''
+import 'dart:async' show Stream;
+import 'package:test/test.dart' as test;
+import 'package:test/other.dart' as o hide SomeClass;
+''',
+    );
+  }
+
   Future<void> test_mixin() async {
     await verifySummary(
       '''