Add a UniqueVector class to GN

tools/gn/builder.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "tools/gn/builder.h"
 
 #include "tools/gn/config.h"
 #include "tools/gn/err.h"
 #include "tools/gn/loader.h"
 #include "tools/gn/scheduler.h"
@@ skipping 210 matching lines @@
   }
 
   return true;
 }
 
 bool Builder::TargetDefined(BuilderRecord* record, Err* err) {
   Target* target = record->item()->AsTarget();
 
   if (!AddDeps(record, target->deps(), err) ||
       !AddDeps(record, target->datadeps(), err) ||
-      !AddDeps(record, target->configs(), err) ||
+      !AddDeps(record, target->configs().vector(), err) ||
       !AddDeps(record, target->all_dependent_configs(), err) ||
       !AddDeps(record, target->direct_dependent_configs(), err) ||
       !AddToolchainDep(record, target, err))
     return false;
 
   // All targets in the default toolchain get generated by default. We also
   // check if this target was previously marked as "required" and force setting
   // the bit again so the target's dependencies (which we now know) get the
   // required bit pushed to them.
   if (record->should_generate() || target->settings()->is_default())
@@ skipping 88 matching lines @@
     BuilderRecord* dep_record = GetOrCreateRecordOfType(
         configs[i].label, configs[i].origin, BuilderRecord::ITEM_CONFIG, err);
     if (!dep_record)
       return false;
     record->AddDep(dep_record);
   }
   return true;
 }
 
 bool Builder::AddDeps(BuilderRecord* record,
+                      const UniqueVector<LabelConfigPair>& configs,
+                      Err* err) {
+  for (size_t i = 0; i < configs.size(); i++) {
+    BuilderRecord* dep_record = GetOrCreateRecordOfType(
+        configs[i].label, configs[i].origin, BuilderRecord::ITEM_CONFIG, err);
+    if (!dep_record)
+      return false;
+    record->AddDep(dep_record);
+  }
+  return true;
+}
+
+bool Builder::AddDeps(BuilderRecord* record,
                       const LabelTargetVector& targets,
                       Err* err) {
   for (size_t i = 0; i < targets.size(); i++) {
     BuilderRecord* dep_record = GetOrCreateRecordOfType(
         targets[i].label, targets[i].origin, BuilderRecord::ITEM_TARGET, err);
     if (!dep_record)
       return false;
     record->AddDep(dep_record);
   }
   return true;
@@ skipping 83 matching lines @@
 
     BuilderRecord* record = GetResolvedRecordOfType(
         cur.label, cur.origin, BuilderRecord::ITEM_TARGET, err);
     if (!record)
       return false;
     cur.ptr = record->item()->AsTarget();
   }
   return true;
 }
 
-bool Builder::ResolveConfigs(LabelConfigVector* configs, Err* err) {
+bool Builder::ResolveConfigs(UniqueVector<LabelConfigPair>* configs, Err* err) {
   for (size_t i = 0; i < configs->size(); i++) {
-    LabelConfigPair& cur = (*configs)[i];
+    const LabelConfigPair& cur = (*configs)[i];
     DCHECK(!cur.ptr);
 
     BuilderRecord* record = GetResolvedRecordOfType(
         cur.label, cur.origin, BuilderRecord::ITEM_CONFIG, err);
     if (!record)
       return false;
-    cur.ptr = record->item()->AsConfig();
+    const_cast<LabelConfigPair&>(cur).ptr = record->item()->AsConfig();
   }
   return true;
 }
 
 // "Forward dependent configs" should refer to targets in the deps that should
 // have their configs forwarded.
 bool Builder::ResolveForwardDependentConfigs(Target* target, Err* err) {
   const LabelTargetVector& deps = target->deps();
-  LabelTargetVector& configs = target->forward_dependent_configs();
+  const UniqueVector<LabelTargetPair>& configs =
+      target->forward_dependent_configs();
 
   // Assume that the lists are small so that brute-force n^2 is appropriate.
   for (size_t config_i = 0; config_i < configs.size(); config_i++) {
     for (size_t dep_i = 0; dep_i < deps.size(); dep_i++) {
       if (configs[config_i].label == deps[dep_i].label) {
         DCHECK(deps[dep_i].ptr);  // Should already be resolved.
-        configs[config_i].ptr = deps[dep_i].ptr;
+        // UniqueVector's contents are constant so uniqueness is preserved, but
+        // we want to update this pointer which doesn't change uniqueness
+        // (uniqueness in this vector is determined by the label only).
+        const_cast<LabelTargetPair&>(configs[config_i]).ptr = deps[dep_i].ptr;
         break;
       }
     }
     if (!configs[config_i].ptr) {
       *err = Err(target->defined_from(),
           "Target in forward_dependent_configs_from was not listed in the deps",
           "This target has a forward_dependent_configs_from entry that was "
           "not present in\nthe deps. A target can only forward things it "
           "depends on. It was forwarding:\n  " +
           configs[config_i].label.GetUserVisibleName(false));
@@ skipping 12 matching lines @@
   // Walk backwards since the dependency arrows point in the reverse direction.
   std::string ret;
   for (int i = static_cast<int>(cycle.size()) - 1; i >= 0; i--) {
     ret += "  " + cycle[i]->label().GetUserVisibleName(false);
     if (i != 0)
       ret += " ->\n";
   }
 
   return ret;
 }