Rangify parser (#176)

Rangify parser
merged-on-behalf-of: BBasile <BBasile@users.noreply.github.com>
This commit is contained in:
Cameron Ross 2018-07-11 23:59:35 -03:00 committed by The Dlang Bot
parent 26eb0913f1
commit 040d19b9bc
6 changed files with 76 additions and 121 deletions

View file

@ -96,21 +96,18 @@ final class Composer
*/
bool checkNode() @safe
{
//Drop the STREAM-START event.
if(parser_.checkEvent(EventID.StreamStart))
{
parser_.getEvent();
}
// If next event is stream start, skip it
parser_.skipOver!"a.id == b"(EventID.StreamStart);
//True if there are more documents available.
return !parser_.checkEvent(EventID.StreamEnd);
return parser_.front.id != EventID.StreamEnd;
}
///Get a YAML document as a node (the root of the document).
Node getNode() @safe
{
//Get the root node of the next document.
assert(!parser_.checkEvent(EventID.StreamEnd),
assert(parser_.front.id != EventID.StreamEnd,
"Trying to get a node from Composer when there is no node to " ~
"get. use checkNode() to determine if there is a node.");
@ -120,25 +117,31 @@ final class Composer
///Get single YAML document, throwing if there is more than one document.
Node getSingleNode() @safe
{
assert(!parser_.checkEvent(EventID.StreamEnd),
assert(parser_.front.id != EventID.StreamEnd,
"Trying to get a node from Composer when there is no node to " ~
"get. use checkNode() to determine if there is a node.");
Node document = composeDocument();
//Ensure that the stream contains no more documents.
enforce(parser_.checkEvent(EventID.StreamEnd),
enforce(parser_.front.id == EventID.StreamEnd,
new ComposerException("Expected single document in the stream, " ~
"but found another document.",
parser_.getEvent().startMark));
parser_.front.startMark));
//Drop the STREAM-END event.
parser_.getEvent();
skipExpected(EventID.StreamEnd);
assert(parser_.empty, "Found event after stream end");
return document;
}
private:
void skipExpected(const EventID id) @safe
{
const foundExpected = parser_.skipOver!"a.id == b"(id);
assert(foundExpected, text("Expected ", id, " not found."));
}
///Ensure that appenders for specified nesting levels exist.
///
///Params: pairAppenderLevel = Current level in the pair appender stack.
@ -159,14 +162,12 @@ final class Composer
///Compose a YAML document and return its root node.
Node composeDocument() @safe
{
//Drop the DOCUMENT-START event.
parser_.getEvent();
skipExpected(EventID.DocumentStart);
//Compose the root node.
Node node = composeNode(0, 0);
//Drop the DOCUMENT-END event.
parser_.getEvent();
skipExpected(EventID.DocumentEnd);
anchors_.destroy();
return node;
@ -178,9 +179,10 @@ final class Composer
/// nodeAppenderLevel = Current level of the node appender stack.
Node composeNode(const uint pairAppenderLevel, const uint nodeAppenderLevel) @safe
{
if(parser_.checkEvent(EventID.Alias))
if(parser_.front.id == EventID.Alias)
{
const event = parser_.getEvent();
const event = parser_.front;
parser_.popFront();
const anchor = event.anchor;
enforce((anchor in anchors_) !is null,
new ComposerException("Found undefined alias: " ~ anchor,
@ -196,7 +198,7 @@ final class Composer
return anchors_[anchor];
}
const event = parser_.peekEvent();
const event = parser_.front;
const anchor = event.anchor;
if((anchor !is null) && (anchor in anchors_) !is null)
{
@ -212,19 +214,19 @@ final class Composer
anchors_[anchor] = Node();
}
if(parser_.checkEvent(EventID.Scalar))
switch (parser_.front.id)
{
case EventID.Scalar:
result = composeScalarNode();
}
else if(parser_.checkEvent(EventID.SequenceStart))
{
break;
case EventID.SequenceStart:
result = composeSequenceNode(pairAppenderLevel, nodeAppenderLevel);
}
else if(parser_.checkEvent(EventID.MappingStart))
{
break;
case EventID.MappingStart:
result = composeMappingNode(pairAppenderLevel, nodeAppenderLevel);
break;
default: assert(false, "This code should never be reached");
}
else{assert(false, "This code should never be reached");}
if(anchor !is null)
{
@ -236,7 +238,8 @@ final class Composer
///Compose a scalar node.
Node composeScalarNode() @safe
{
const event = parser_.getEvent();
const event = parser_.front;
parser_.popFront();
const tag = resolver_.resolve(NodeID.Scalar, event.tag, event.value,
event.implicit);
@ -256,17 +259,19 @@ final class Composer
ensureAppendersExist(pairAppenderLevel, nodeAppenderLevel);
auto nodeAppender = &(nodeAppenders_[nodeAppenderLevel]);
const startEvent = parser_.getEvent();
const startEvent = parser_.front;
parser_.popFront();
const tag = resolver_.resolve(NodeID.Sequence, startEvent.tag, null,
startEvent.implicit);
while(!parser_.checkEvent(EventID.SequenceEnd))
while(parser_.front.id != EventID.SequenceEnd)
{
nodeAppender.put(composeNode(pairAppenderLevel, nodeAppenderLevel + 1));
}
Node node = constructor_.node(startEvent.startMark, parser_.getEvent().endMark,
Node node = constructor_.node(startEvent.startMark, parser_.front.endMark,
tag, nodeAppender.data.dup, startEvent.collectionStyle);
parser_.popFront();
nodeAppender.clear();
return node;
@ -351,13 +356,14 @@ final class Composer
@safe
{
ensureAppendersExist(pairAppenderLevel, nodeAppenderLevel);
const startEvent = parser_.getEvent();
const startEvent = parser_.front;
parser_.popFront();
const tag = resolver_.resolve(NodeID.Mapping, startEvent.tag, null,
startEvent.implicit);
auto pairAppender = &(pairAppenders_[pairAppenderLevel]);
Tuple!(Node, Mark)[] toMerge;
while(!parser_.checkEvent(EventID.MappingEnd))
while(parser_.front.id != EventID.MappingEnd)
{
auto pair = Node.Pair(composeNode(pairAppenderLevel + 1, nodeAppenderLevel),
composeNode(pairAppenderLevel + 1, nodeAppenderLevel));
@ -365,7 +371,7 @@ final class Composer
//Need to flatten and merge the node referred by YAMLMerge.
if(pair.key.isType!YAMLMerge)
{
toMerge ~= tuple(pair.value, cast(Mark)parser_.peekEvent().endMark);
toMerge ~= tuple(pair.value, cast(Mark)parser_.front.endMark);
}
//Not YAMLMerge, just add the pair.
else
@ -383,10 +389,11 @@ final class Composer
.uniq!((x,y) => x.key == y.key)
.walkLength;
enforce(numUnique == pairAppender.data.length,
new ComposerException("Duplicate key found in mapping", parser_.getEvent().startMark));
new ComposerException("Duplicate key found in mapping", parser_.front.startMark));
Node node = constructor_.node(startEvent.startMark, parser_.getEvent().endMark,
Node node = constructor_.node(startEvent.startMark, parser_.front.endMark,
tag, pairAppender.data.dup, startEvent.collectionStyle);
parser_.popFront();
pairAppender.clear();
return node;

View file

@ -237,7 +237,8 @@ struct Dumper(Range)
*
* Throws: YAMLException if unable to emit.
*/
void emit(CharacterType = char)(Event[] events) @safe
void emit(CharacterType = char, T)(T events) @safe
if (isInputRange!T && is(ElementType!T == Event))
{
try
{

View file

@ -317,22 +317,9 @@ struct Loader
// Parse and return all events. Used for debugging.
Event[] parse() @safe
auto parse() @safe
{
try
{
Event[] result;
while(parser_.checkEvent())
{
result ~= parser_.getEvent();
}
return result;
}
catch(YAMLException e)
{
throw new YAMLException("Unable to parse YAML from stream %s : %s "
.format(name_, e.msg));
}
return parser_;
}
// Construct default constructor/resolver if the user has not yet specified

View file

@ -142,78 +142,46 @@ final class Parser
}
/**
* Check if the next event is one of specified types.
*
* If no types are specified, checks if any events are left.
*
* Params: ids = Event IDs to check for.
*
* Returns: true if the next event is one of specified types,
* or if there are any events left if no types specified.
* false otherwise.
* Check if any events are left. May have side effects in some cases.
*/
bool checkEvent(EventID[] ids...) @safe
bool empty() @safe
{
//Check if the next event is one of specified types.
if(currentEvent_.isNull && state_ !is null)
{
currentEvent_ = state_();
}
if(!currentEvent_.isNull)
{
if(ids.length == 0){return true;}
else
{
const nextId = currentEvent_.id;
foreach(id; ids)
{
if(nextId == id){return true;}
}
}
}
return false;
ensureState();
return currentEvent_.isNull;
}
/**
* Return the next event, but keep it in the queue.
* Return the current event.
*
* Must not be called if there are no events left.
*/
Event peekEvent() @safe
Event front() @safe
{
if(currentEvent_.isNull && state_ !is null)
{
currentEvent_ = state_();
}
if(!currentEvent_.isNull){return currentEvent_;}
assert(false, "No event left to peek");
ensureState();
assert(!currentEvent_.isNull, "No event left to peek");
return currentEvent_;
}
/**
* Return the next event, removing it from the queue.
* Skip to the next event.
*
* Must not be called if there are no events left.
*/
Event getEvent() @safe
void popFront() @safe
{
//Get the next event and proceed further.
if(currentEvent_.isNull && state_ !is null)
{
currentEvent_ = state_();
}
if(!currentEvent_.isNull)
{
Event result = currentEvent_;
currentEvent_.id = EventID.Invalid;
return result;
}
assert(false, "No event left to get");
ensureState();
}
private:
/// If current event is invalid, load the next valid one if possible.
void ensureState() @safe
{
if(currentEvent_.isNull && state_ !is null)
{
currentEvent_ = state_();
}
}
///Pop and return the newest state in states_.
Event delegate() @safe popState() @safe
{

View file

@ -11,6 +11,7 @@ version(unittest)
{
import dyaml.test.common;
import dyaml.test.emitter;
import dyaml.token;
@ -23,12 +24,7 @@ void testParser(string dataFilename, string canonicalFilename) @safe
auto dataEvents = Loader.fromFile(dataFilename).parse();
auto canonicalEvents = Loader.fromFile(canonicalFilename).parse();
assert(dataEvents.length == canonicalEvents.length);
foreach(e; 0 .. dataEvents.length)
{
assert(dataEvents[e].id == canonicalEvents[e].id);
}
compareEvents(dataEvents, canonicalEvents);
}

View file

@ -27,15 +27,11 @@ import dyaml.token;
/// events2 = Second event array to compare.
///
/// Returns: true if the events are equivalent, false otherwise.
bool compareEvents(Event[] events1, Event[] events2) @safe
bool compareEvents(T, U)(T events1, U events2)
if (isInputRange!T && isInputRange!U && is(ElementType!T == Event) && is(ElementType!U == Event))
{
if(events1.length != events2.length){return false;}
for(uint e; e < events1.length; ++e)
foreach (e1, e2; zip(events1, events2))
{
auto e1 = events1[e];
auto e2 = events2[e];
//Different event types.
if(e1.id != e2.id){return false;}
//Different anchor (if applicable).