tools/gn/scope.cc - third_party/gn - Git at Google

 // 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/scope.h"

 #include "base/logging.h"
 #include "base/stl_util.h"
 #include "tools/gn/parse_tree.h"

 namespace {

 // FLags set in the mode_flags_ of a scope. If a bit is set, it applies
 // recursively to all dependent scopes.
 const unsigned kProcessingBuildConfigFlag = 1;
 const unsigned kProcessingDefaultBuildConfigFlag = 2;
 const unsigned kProcessingImportFlag = 4;

 }  // namespace

 Scope::Scope(const Settings* settings)
     : const_containing_(NULL),
       mutable_containing_(NULL),
       settings_(settings),
       mode_flags_(0) {
 }

 Scope::Scope(Scope* parent)
     : const_containing_(NULL),
       mutable_containing_(parent),
       settings_(parent->settings()),
       mode_flags_(0) {
 }

 Scope::Scope(const Scope* parent)
     : const_containing_(parent),
       mutable_containing_(NULL),
       settings_(parent->settings()),
       mode_flags_(0) {
 }

 Scope::~Scope() {
   STLDeleteContainerPairSecondPointers(target_defaults_.begin(),
                                        target_defaults_.end());
 }

 const Value* Scope::GetValue(const base::StringPiece& ident,
                              bool counts_as_used) {
   // First check for programatically-provided values.
   for (ProviderSet::const_iterator i = programmatic_providers_.begin();
        i != programmatic_providers_.end(); ++i) {
     const Value* v = (*i)->GetProgrammaticValue(ident);
     if (v)
       return v;
   }

   RecordMap::iterator found = values_.find(ident);
   if (found != values_.end()) {
     if (counts_as_used)
       found->second.used = true;
     return &found->second.value;
   }

   // Search in the parent scope.
   if (const_containing_)
     return const_containing_->GetValue(ident);
   if (mutable_containing_)
     return mutable_containing_->GetValue(ident, counts_as_used);
   return NULL;
 }

 Value* Scope::GetValueForcedToCurrentScope(const base::StringPiece& ident,
                                            const ParseNode* set_node) {
   RecordMap::iterator found = values_.find(ident);
   if (found != values_.end())
     return &found->second.value;  // Already have in the current scope.

   // Search in the parent scope.
   if (containing()) {
     const Value* in_containing = containing()->GetValue(ident);
     if (in_containing) {
       // Promote to current scope.
       return SetValue(ident, *in_containing, set_node);
     }
   }
   return NULL;
 }

 const Value* Scope::GetValue(const base::StringPiece& ident) const {
   RecordMap::const_iterator found = values_.find(ident);
   if (found != values_.end())
     return &found->second.value;
   if (containing())
     return containing()->GetValue(ident);
   return NULL;
 }

 Value* Scope::SetValue(const base::StringPiece& ident,
                        const Value& v,
                        const ParseNode* set_node) {
   Record& r = values_[ident];  // Clears any existing value.
   r.value = v;
   r.value.set_origin(set_node);
   return &r.value;
 }

 bool Scope::AddTemplate(const std::string& name, const FunctionCallNode* decl) {
   if (GetTemplate(name))
     return false;
   templates_[name] = decl;
   return true;
 }

 const FunctionCallNode* Scope::GetTemplate(const std::string& name) const {
   TemplateMap::const_iterator found = templates_.find(name);
   if (found != templates_.end())
     return found->second;
   if (containing())
     return containing()->GetTemplate(name);
   return NULL;
 }

 void Scope::MarkUsed(const base::StringPiece& ident) {
   RecordMap::iterator found = values_.find(ident);
   if (found == values_.end()) {
     NOTREACHED();
     return;
   }
   found->second.used = true;
 }

 void Scope::MarkUnused(const base::StringPiece& ident) {
   RecordMap::iterator found = values_.find(ident);
   if (found == values_.end()) {
     NOTREACHED();
     return;
   }
   found->second.used = false;
 }

 bool Scope::IsSetButUnused(const base::StringPiece& ident) const {
   RecordMap::const_iterator found = values_.find(ident);
   if (found != values_.end()) {
     if (!found->second.used) {
       return true;
     }
   }
   return false;
 }

 bool Scope::CheckForUnusedVars(Err* err) const {
   for (RecordMap::const_iterator i = values_.begin();
        i != values_.end(); ++i) {
     if (!i->second.used) {
       std::string help = "You set the variable \"" + i->first.as_string() +
           "\" here and it was unused before it went\nout of scope.";

       const BinaryOpNode* binary = i->second.value.origin()->AsBinaryOp();
       if (binary) {
         // Make a nicer error message for normal var sets.
         *err = Err(binary->left()->GetRange(), "Assignment had no effect.",
                    help);
       } else {
         // This will happen for internally-generated variables.
         *err = Err(i->second.value.origin(), "Assignment had no effect.", help);
       }
       return false;
     }
   }
   return true;
 }

 void Scope::GetCurrentScopeValues(KeyValueVector* output) const {
   output->reserve(values_.size());
   for (RecordMap::const_iterator i = values_.begin(); i != values_.end(); ++i) {
     output->push_back(std::make_pair(i->first, i->second.value));
   }
 }

 bool Scope::NonRecursiveMergeTo(Scope* dest,
                                 const ParseNode* node_for_err,
                                 const char* desc_for_err,
                                 Err* err) const {
   // Values.
   for (RecordMap::const_iterator i = values_.begin(); i != values_.end(); ++i) {
     const Value* existing_value = dest->GetValue(i->first);
     if (existing_value) {
       // Value present in both the source and the dest.
       std::string desc_string(desc_for_err);
       *err = Err(node_for_err, "Value collision.",
           "This " + desc_string + " contains \"" + i->first.as_string() + "\"");
       err->AppendSubErr(Err(i->second.value, "defined here.",
           "Which would clobber the one in your current scope"));
       err->AppendSubErr(Err(*existing_value, "defined here.",
           "Executing " + desc_string + " should not conflict with anything "
           "in the current\nscope."));
       return false;
     }
     dest->values_[i->first] = i->second;
   }

   // Target defaults are owning pointers.
   for (NamedScopeMap::const_iterator i = target_defaults_.begin();
        i != target_defaults_.end(); ++i) {
     if (dest->GetTargetDefaults(i->first)) {
       // TODO(brettw) it would be nice to know the origin of a
       // set_target_defaults so we can give locations for the colliding target
       // defaults.
       std::string desc_string(desc_for_err);
       *err = Err(node_for_err, "Target defaults collision.",
           "This " + desc_string + " contains target defaults for\n"
           "\"" + i->first + "\" which would clobber one for the\n"
           "same target type in your current scope. It's unfortunate that I'm "
           "too stupid\nto tell you the location of where the target defaults "
           "were set. Usually\nthis happens in the BUILDCONFIG.gn file.");
       return false;
     }

     Scope* s = new Scope(settings_);
     i->second->NonRecursiveMergeTo(s, node_for_err, "<SHOULDN'T HAPPEN>", err);
     dest->target_defaults_[i->first] = s;
   }

   // Sources assignment filter.
   if (sources_assignment_filter_) {
     if (dest->GetSourcesAssignmentFilter()) {
       // Sources assignment filter present in both the source and the dest.
       std::string desc_string(desc_for_err);
       *err = Err(node_for_err, "Assignment filter collision.",
           "The " + desc_string + " contains a sources_assignment_filter which\n"
           "would clobber the one in your current scope.");
       return false;
     }
     dest->sources_assignment_filter_.reset(
         new PatternList(*sources_assignment_filter_));
   }

   // Templates.
   for (TemplateMap::const_iterator i = templates_.begin();
        i != templates_.end(); ++i) {
     const FunctionCallNode* existing_template = dest->GetTemplate(i->first);
     if (existing_template) {
       // Rule present in both the source and the dest.
       std::string desc_string(desc_for_err);
       *err = Err(node_for_err, "Template collision.",
           "This " + desc_string + " contains a template \"" + i->first + "\"");
       err->AppendSubErr(Err(i->second->function(), "defined here.",
           "Which would clobber the one in your current scope"));
       err->AppendSubErr(Err(existing_template->function(), "defined here.",
           "Executing " + desc_string + " should not conflict with anything "
           "in the current\nscope."));
       return false;
     }
     dest->templates_.insert(*i);
   }

   return true;
 }

 Scope* Scope::MakeTargetDefaults(const std::string& target_type) {
   if (GetTargetDefaults(target_type))
     return NULL;

   Scope** dest = &target_defaults_[target_type];
   if (*dest) {
     NOTREACHED();  // Already set.
     return *dest;
   }
   *dest = new Scope(settings_);
   return *dest;
 }

 const Scope* Scope::GetTargetDefaults(const std::string& target_type) const {
   NamedScopeMap::const_iterator found = target_defaults_.find(target_type);
   if (found != target_defaults_.end())
     return found->second;
   if (containing())
     return containing()->GetTargetDefaults(target_type);
   return NULL;
 }

 const PatternList* Scope::GetSourcesAssignmentFilter() const {
   if (sources_assignment_filter_)
     return sources_assignment_filter_.get();
   if (containing())
     return containing()->GetSourcesAssignmentFilter();
   return NULL;
 }

 void Scope::SetProcessingBuildConfig() {
   DCHECK((mode_flags_ & kProcessingBuildConfigFlag) == 0);
   mode_flags_ |= kProcessingBuildConfigFlag;
 }

 void Scope::ClearProcessingBuildConfig() {
   DCHECK(mode_flags_ & kProcessingBuildConfigFlag);
   mode_flags_ &= ~(kProcessingBuildConfigFlag);
 }

 bool Scope::IsProcessingBuildConfig() const {
   if (mode_flags_ & kProcessingBuildConfigFlag)
     return true;
   if (containing())
     return containing()->IsProcessingBuildConfig();
   return false;
 }

 void Scope::SetProcessingDefaultBuildConfig() {
   DCHECK((mode_flags_ & kProcessingDefaultBuildConfigFlag) == 0);
   mode_flags_ |= kProcessingDefaultBuildConfigFlag;
 }

 void Scope::ClearProcessingDefaultBuildConfig() {
   DCHECK(mode_flags_ & kProcessingDefaultBuildConfigFlag);
   mode_flags_ &= ~(kProcessingDefaultBuildConfigFlag);
 }

 bool Scope::IsProcessingDefaultBuildConfig() const {
   if (mode_flags_ & kProcessingDefaultBuildConfigFlag)
     return true;
   if (containing())
     return containing()->IsProcessingDefaultBuildConfig();
   return false;
 }

 void Scope::SetProcessingImport() {
   DCHECK((mode_flags_ & kProcessingImportFlag) == 0);
   mode_flags_ |= kProcessingImportFlag;
 }

 void Scope::ClearProcessingImport() {
   DCHECK(mode_flags_ & kProcessingImportFlag);
   mode_flags_ &= ~(kProcessingImportFlag);
 }

 bool Scope::IsProcessingImport() const {
   if (mode_flags_ & kProcessingImportFlag)
     return true;
   if (containing())
     return containing()->IsProcessingImport();
   return false;
 }

 void Scope::SetProperty(const void* key, void* value) {
   if (!value) {
     DCHECK(properties_.find(key) != properties_.end());
     properties_.erase(key);
   } else {
     properties_[key] = value;
   }
 }

 void* Scope::GetProperty(const void* key, const Scope** found_on_scope) const {
   PropertyMap::const_iterator found = properties_.find(key);
   if (found != properties_.end()) {
     if (found_on_scope)
       *found_on_scope = this;
     return found->second;
   }
   if (containing())
     return containing()->GetProperty(key, found_on_scope);
   return NULL;
 }

 void Scope::AddProvider(ProgrammaticProvider* p) {
   programmatic_providers_.insert(p);
 }

 void Scope::RemoveProvider(ProgrammaticProvider* p) {
   DCHECK(programmatic_providers_.find(p) != programmatic_providers_.end());
   programmatic_providers_.erase(p);
 }
	// 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/scope.h"

	#include "base/logging.h"
	#include "base/stl_util.h"
	#include "tools/gn/parse_tree.h"

	namespace {

	// FLags set in the mode_flags_ of a scope. If a bit is set, it applies
	// recursively to all dependent scopes.
	const unsigned kProcessingBuildConfigFlag = 1;
	const unsigned kProcessingDefaultBuildConfigFlag = 2;
	const unsigned kProcessingImportFlag = 4;

	} // namespace

	Scope::Scope(const Settings* settings)
	: const_containing_(NULL),
	mutable_containing_(NULL),
	settings_(settings),
	mode_flags_(0) {
	}

	Scope::Scope(Scope* parent)
	: const_containing_(NULL),
	mutable_containing_(parent),
	settings_(parent->settings()),
	mode_flags_(0) {
	}

	Scope::Scope(const Scope* parent)
	: const_containing_(parent),
	mutable_containing_(NULL),
	settings_(parent->settings()),
	mode_flags_(0) {
	}

	Scope::~Scope() {
	STLDeleteContainerPairSecondPointers(target_defaults_.begin(),
	target_defaults_.end());
	}

	const Value* Scope::GetValue(const base::StringPiece& ident,
	bool counts_as_used) {
	// First check for programatically-provided values.
	for (ProviderSet::const_iterator i = programmatic_providers_.begin();
	i != programmatic_providers_.end(); ++i) {
	const Value* v = (*i)->GetProgrammaticValue(ident);
	if (v)
	return v;
	}

	RecordMap::iterator found = values_.find(ident);
	if (found != values_.end()) {
	if (counts_as_used)
	found->second.used = true;
	return &found->second.value;
	}

	// Search in the parent scope.
	if (const_containing_)
	return const_containing_->GetValue(ident);
	if (mutable_containing_)
	return mutable_containing_->GetValue(ident, counts_as_used);
	return NULL;
	}

	Value* Scope::GetValueForcedToCurrentScope(const base::StringPiece& ident,
	const ParseNode* set_node) {
	RecordMap::iterator found = values_.find(ident);
	if (found != values_.end())
	return &found->second.value; // Already have in the current scope.

	// Search in the parent scope.
	if (containing()) {
	const Value* in_containing = containing()->GetValue(ident);
	if (in_containing) {
	// Promote to current scope.
	return SetValue(ident, *in_containing, set_node);
	}
	}
	return NULL;
	}

	const Value* Scope::GetValue(const base::StringPiece& ident) const {
	RecordMap::const_iterator found = values_.find(ident);
	if (found != values_.end())
	return &found->second.value;
	if (containing())
	return containing()->GetValue(ident);
	return NULL;
	}

	Value* Scope::SetValue(const base::StringPiece& ident,
	const Value& v,
	const ParseNode* set_node) {
	Record& r = values_[ident]; // Clears any existing value.
	r.value = v;
	r.value.set_origin(set_node);
	return &r.value;
	}

	bool Scope::AddTemplate(const std::string& name, const FunctionCallNode* decl) {
	if (GetTemplate(name))
	return false;
	templates_[name] = decl;
	return true;
	}

	const FunctionCallNode* Scope::GetTemplate(const std::string& name) const {
	TemplateMap::const_iterator found = templates_.find(name);
	if (found != templates_.end())
	return found->second;
	if (containing())
	return containing()->GetTemplate(name);
	return NULL;
	}

	void Scope::MarkUsed(const base::StringPiece& ident) {
	RecordMap::iterator found = values_.find(ident);
	if (found == values_.end()) {
	NOTREACHED();
	return;
	}
	found->second.used = true;
	}

	void Scope::MarkUnused(const base::StringPiece& ident) {
	RecordMap::iterator found = values_.find(ident);
	if (found == values_.end()) {
	NOTREACHED();
	return;
	}
	found->second.used = false;
	}

	bool Scope::IsSetButUnused(const base::StringPiece& ident) const {
	RecordMap::const_iterator found = values_.find(ident);
	if (found != values_.end()) {
	if (!found->second.used) {
	return true;
	}
	}
	return false;
	}

	bool Scope::CheckForUnusedVars(Err* err) const {
	for (RecordMap::const_iterator i = values_.begin();
	i != values_.end(); ++i) {
	if (!i->second.used) {
	std::string help = "You set the variable \"" + i->first.as_string() +
	"\" here and it was unused before it went\nout of scope.";

	const BinaryOpNode* binary = i->second.value.origin()->AsBinaryOp();
	if (binary) {
	// Make a nicer error message for normal var sets.
	*err = Err(binary->left()->GetRange(), "Assignment had no effect.",
	help);
	} else {
	// This will happen for internally-generated variables.
	*err = Err(i->second.value.origin(), "Assignment had no effect.", help);
	}
	return false;
	}
	}
	return true;
	}

	void Scope::GetCurrentScopeValues(KeyValueVector* output) const {
	output->reserve(values_.size());
	for (RecordMap::const_iterator i = values_.begin(); i != values_.end(); ++i) {
	output->push_back(std::make_pair(i->first, i->second.value));
	}
	}

	bool Scope::NonRecursiveMergeTo(Scope* dest,
	const ParseNode* node_for_err,
	const char* desc_for_err,
	Err* err) const {
	// Values.
	for (RecordMap::const_iterator i = values_.begin(); i != values_.end(); ++i) {
	const Value* existing_value = dest->GetValue(i->first);
	if (existing_value) {
	// Value present in both the source and the dest.
	std::string desc_string(desc_for_err);
	*err = Err(node_for_err, "Value collision.",
	"This " + desc_string + " contains \"" + i->first.as_string() + "\"");
	err->AppendSubErr(Err(i->second.value, "defined here.",
	"Which would clobber the one in your current scope"));
	err->AppendSubErr(Err(*existing_value, "defined here.",
	"Executing " + desc_string + " should not conflict with anything "
	"in the current\nscope."));
	return false;
	}
	dest->values_[i->first] = i->second;
	}

	// Target defaults are owning pointers.
	for (NamedScopeMap::const_iterator i = target_defaults_.begin();
	i != target_defaults_.end(); ++i) {
	if (dest->GetTargetDefaults(i->first)) {
	// TODO(brettw) it would be nice to know the origin of a
	// set_target_defaults so we can give locations for the colliding target
	// defaults.
	std::string desc_string(desc_for_err);
	*err = Err(node_for_err, "Target defaults collision.",
	"This " + desc_string + " contains target defaults for\n"
	"\"" + i->first + "\" which would clobber one for the\n"
	"same target type in your current scope. It's unfortunate that I'm "
	"too stupid\nto tell you the location of where the target defaults "
	"were set. Usually\nthis happens in the BUILDCONFIG.gn file.");
	return false;
	}

	Scope* s = new Scope(settings_);
	i->second->NonRecursiveMergeTo(s, node_for_err, "<SHOULDN'T HAPPEN>", err);
	dest->target_defaults_[i->first] = s;
	}

	// Sources assignment filter.
	if (sources_assignment_filter_) {
	if (dest->GetSourcesAssignmentFilter()) {
	// Sources assignment filter present in both the source and the dest.
	std::string desc_string(desc_for_err);
	*err = Err(node_for_err, "Assignment filter collision.",
	"The " + desc_string + " contains a sources_assignment_filter which\n"
	"would clobber the one in your current scope.");
	return false;
	}
	dest->sources_assignment_filter_.reset(
	new PatternList(*sources_assignment_filter_));
	}

	// Templates.
	for (TemplateMap::const_iterator i = templates_.begin();
	i != templates_.end(); ++i) {
	const FunctionCallNode* existing_template = dest->GetTemplate(i->first);
	if (existing_template) {
	// Rule present in both the source and the dest.
	std::string desc_string(desc_for_err);
	*err = Err(node_for_err, "Template collision.",
	"This " + desc_string + " contains a template \"" + i->first + "\"");
	err->AppendSubErr(Err(i->second->function(), "defined here.",
	"Which would clobber the one in your current scope"));
	err->AppendSubErr(Err(existing_template->function(), "defined here.",
	"Executing " + desc_string + " should not conflict with anything "
	"in the current\nscope."));
	return false;
	}
	dest->templates_.insert(*i);
	}

	return true;
	}

	Scope* Scope::MakeTargetDefaults(const std::string& target_type) {
	if (GetTargetDefaults(target_type))
	return NULL;

	Scope** dest = &target_defaults_[target_type];
	if (*dest) {
	NOTREACHED(); // Already set.
	return *dest;
	}
	*dest = new Scope(settings_);
	return *dest;
	}

	const Scope* Scope::GetTargetDefaults(const std::string& target_type) const {
	NamedScopeMap::const_iterator found = target_defaults_.find(target_type);
	if (found != target_defaults_.end())
	return found->second;
	if (containing())
	return containing()->GetTargetDefaults(target_type);
	return NULL;
	}

	const PatternList* Scope::GetSourcesAssignmentFilter() const {
	if (sources_assignment_filter_)
	return sources_assignment_filter_.get();
	if (containing())
	return containing()->GetSourcesAssignmentFilter();
	return NULL;
	}

	void Scope::SetProcessingBuildConfig() {
	DCHECK((mode_flags_ & kProcessingBuildConfigFlag) == 0);
	mode_flags_ \|= kProcessingBuildConfigFlag;
	}

	void Scope::ClearProcessingBuildConfig() {
	DCHECK(mode_flags_ & kProcessingBuildConfigFlag);
	mode_flags_ &= ~(kProcessingBuildConfigFlag);
	}

	bool Scope::IsProcessingBuildConfig() const {
	if (mode_flags_ & kProcessingBuildConfigFlag)
	return true;
	if (containing())
	return containing()->IsProcessingBuildConfig();
	return false;
	}

	void Scope::SetProcessingDefaultBuildConfig() {
	DCHECK((mode_flags_ & kProcessingDefaultBuildConfigFlag) == 0);
	mode_flags_ \|= kProcessingDefaultBuildConfigFlag;
	}

	void Scope::ClearProcessingDefaultBuildConfig() {
	DCHECK(mode_flags_ & kProcessingDefaultBuildConfigFlag);
	mode_flags_ &= ~(kProcessingDefaultBuildConfigFlag);
	}

	bool Scope::IsProcessingDefaultBuildConfig() const {
	if (mode_flags_ & kProcessingDefaultBuildConfigFlag)
	return true;
	if (containing())
	return containing()->IsProcessingDefaultBuildConfig();
	return false;
	}

	void Scope::SetProcessingImport() {
	DCHECK((mode_flags_ & kProcessingImportFlag) == 0);
	mode_flags_ \|= kProcessingImportFlag;
	}

	void Scope::ClearProcessingImport() {
	DCHECK(mode_flags_ & kProcessingImportFlag);
	mode_flags_ &= ~(kProcessingImportFlag);
	}

	bool Scope::IsProcessingImport() const {
	if (mode_flags_ & kProcessingImportFlag)
	return true;
	if (containing())
	return containing()->IsProcessingImport();
	return false;
	}

	void Scope::SetProperty(const void* key, void* value) {
	if (!value) {
	DCHECK(properties_.find(key) != properties_.end());
	properties_.erase(key);
	} else {
	properties_[key] = value;
	}
	}

	void* Scope::GetProperty(const void* key, const Scope** found_on_scope) const {
	PropertyMap::const_iterator found = properties_.find(key);
	if (found != properties_.end()) {
	if (found_on_scope)
	*found_on_scope = this;
	return found->second;
	}
	if (containing())
	return containing()->GetProperty(key, found_on_scope);
	return NULL;
	}

	void Scope::AddProvider(ProgrammaticProvider* p) {
	programmatic_providers_.insert(p);
	}

	void Scope::RemoveProvider(ProgrammaticProvider* p) {
	DCHECK(programmatic_providers_.find(p) != programmatic_providers_.end());
	programmatic_providers_.erase(p);
	}