Draft: Add support for adding constructor

src/codeaction/implementconstructoraction.vala

@@ -0,0 +1,62 @@
+/* implementconstructoraction.vala
+ *
+ * Copyright 2022 JCWasmx86 <[email protected]>
+ *
+ * This file is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of the
+ * License, or (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+using Lsp;
+using Gee;
+
+class Vls.ImplementConstructorAction : CodeAction {
+    public ImplementConstructorAction (Vala.ObjectCreationExpression oce, Vala.Symbol to_be_created) {
+        var target_file = to_be_created.source_reference.file;
+        var insertion_line = to_be_created.source_reference.end.line + 1;
+        var sb = new StringBuilder ();
+        var indent = to_be_created.source_reference.begin.column == 1 ? "" : "\t";
+        sb.append (indent).append (indent).append ("public ").append (oce.member_name.to_string ()).append (" (");
+        var args = oce.get_argument_list ();
+        var idx = 0;
+        for (var i = 0; i < args.size - 1; i++) {
+            sb.append (args[i].value_type.to_string ()).append (" arg%d".printf (idx++)).append (", ");
+        }
+        if (args.size != 0)
+            sb.append (args[args.size - 1].value_type.to_string ()).append (" arg%d".printf (idx));
+        sb.append (") {}\n ");
+        try {
+            var target_uri = Filename.to_uri (target_file.filename);
+            var target_document = new VersionedTextDocumentIdentifier () {
+                uri = target_uri,
+                version = 1
+            };
+            var workspace_edit = new WorkspaceEdit ();
+            var document_edit = new TextDocumentEdit (target_document);
+            var r = new Range.from_sourceref (
+                new Vala.SourceReference (target_file,
+                                          Vala.SourceLocation (null, insertion_line, 1),
+                                          Vala.SourceLocation (null, insertion_line, 1)));
+            var text_edit = new TextEdit (r);
+            document_edit.edits.add (text_edit);
+            workspace_edit.documentChanges = new Gee.ArrayList<TextDocumentEdit> ();
+            workspace_edit.documentChanges.add (document_edit);
+            this.edit = workspace_edit;
+            this.title = "Add constructor";
+            text_edit.newText = sb.str;
+        } catch (ConvertError ce) {
+            error ("Should not happen: %s", ce.message);
+        }
+    }
+}

src/codehelp/codeaction.vala

@@ -23,13 +23,13 @@ using Vala;
 
 namespace Vls.CodeActions {
     /**
-     * Extracts a list of code actions for the given document and range.
+     * Extracts a list of code actions for the given document and range using the AST and the diagnostics.
      *
      * @param file      the current document
      * @param range     the range to show code actions for
      * @param uri       the document URI
      */
-    Collection<CodeAction> extract (Compilation compilation, TextDocument file, Range range, string uri) {
+    Collection<CodeAction> generate_codeactions (Compilation compilation, TextDocument file, Range range, string uri, Reporter reporter) {
         // search for nodes containing the query range
         var finder = new NodeSearch (file, range.start, true, range.end);
         var code_actions = new ArrayList<CodeAction> ();
@@ -41,13 +41,14 @@ namespace Vls.CodeActions {
 
         // add code actions
         foreach (CodeNode code_node in finder.result) {
+            critical ("%s", code_node.type_name);
             if (code_node is IntegerLiteral) {
-                var lit = (IntegerLiteral)code_node;
+                var lit = (IntegerLiteral) code_node;
                 var lit_range = new Range.from_sourceref (lit.source_reference);
                 if (lit_range.contains (range.start) && lit_range.contains (range.end))
                     code_actions.add (new BaseConverterAction (lit, document));
             } else if (code_node is Class) {
-                var csym = (Class)code_node;
+                var csym = (Class) code_node;
                 var clsdef_range = compute_class_def_range (csym, class_ranges);
                 var cls_range = new Range.from_sourceref (csym.source_reference);
                 if (cls_range.contains (range.start) && cls_range.contains (range.end)) {
@@ -57,6 +58,29 @@ namespace Vls.CodeActions {
                         code_actions.add (new ImplementMissingPrereqsAction (csym, missing.first, missing.second, clsdef_range.end, code_style, document));
                     }
                 }
+            } else if (code_node is ObjectCreationExpression) {
+                var oce = (ObjectCreationExpression) code_node;
+                foreach (var diag in reporter.messages) {
+                    if (file.filename != diag.loc.file.filename)
+                        continue;
+                    if (!(oce.source_reference.contains (diag.loc.begin) || oce.source_reference.contains (diag.loc.end)))
+                        continue;
+                    if (diag.message.contains (" extra arguments for ")) {
+                        var to_be_created = oce.type_reference.symbol;
+                        if (!(to_be_created is Vala.Class)) {
+                            continue;
+                        }
+                        var constr = ((Vala.Class) to_be_created).constructor;
+                        if (constr != null) {
+                            continue;
+                        }
+                        var target_file = to_be_created.source_reference.file;
+                        // We can't just edit, e.g. some external vapi
+                        if (!compilation.get_project_files ().contains (target_file))
+                            continue;
+                        code_actions.add (new ImplementConstructorAction (oce, to_be_created));
+                    }
+                }
             }
         }
 
@@ -72,11 +96,11 @@ namespace Vls.CodeActions {
         // otherwise compute the result and cache it
         // csym.source_reference must be non-null otherwise NodeSearch wouldn't have found csym
         var pos = new Position.from_libvala (csym.source_reference.end);
-        var offset = csym.source_reference.end.pos - (char *)csym.source_reference.file.content;
+        var offset = csym.source_reference.end.pos - (char*) csym.source_reference.file.content;
         var dl = 0;
         var dc = 0;
-        while (offset < csym.source_reference.file.content.length && csym.source_reference.file.content[(long)offset] != '{') {
-            if (Util.is_newline (csym.source_reference.file.content[(long)offset])) {
+        while (offset < csym.source_reference.file.content.length && csym.source_reference.file.content[(long) offset] != '{') {
+            if (Util.is_newline (csym.source_reference.file.content[(long) offset])) {
                 dl++;
                 dc = 0;
             } else {
@@ -93,8 +117,8 @@ namespace Vls.CodeActions {
             if (member.source_reference == null)
                 continue;
             range = range.union (new Range.from_sourceref (member.source_reference));
-            if (member is Method && ((Method)member).body != null && ((Method)member).body.source_reference != null)
-                range = range.union (new Range.from_sourceref (((Method)member).body.source_reference));
+            if (member is Method && ((Method) member).body != null && ((Method) member).body.source_reference != null)
+                range = range.union (new Range.from_sourceref (((Method) member).body.source_reference));
         }
         class_ranges[csym] = range;
         return range;

src/meson.build

@@ -4,6 +4,7 @@ vls_src = files([
   'analysis/codestyleanalyzer.vala',
   'analysis/symbolenumerator.vala',
   'codeaction/baseconverteraction.vala',
+  'codeaction/implementconstructoraction.vala',
   'codeaction/implementmissingprereqsaction.vala',
   'codehelp/callhierarchy.vala',
   'codehelp/codeaction.vala',

src/server.vala

@@ -1645,7 +1645,7 @@ class Vls.Server : Jsonrpc.Server {
         var json_array = new Json.Array ();
 
         Vala.CodeContext.push (compilation.code_context);
-        var code_actions = CodeActions.extract (compilation, (TextDocument) source_file, p.range, Uri.unescape_string (p.textDocument.uri));
+        var code_actions = CodeActions.generate_codeactions (compilation, (TextDocument) source_file, p.range, Uri.unescape_string (p.textDocument.uri), compilation.reporter);
         foreach (var action in code_actions)
             json_array.add_element (Json.gobject_serialize (action));
         Vala.CodeContext.pop ();