protected override Expression VisitBlockHelperExpression(BlockHelperExpression bhex)
{
var fb = new FunctionBuilder(CompilationContext.Configuration);
var body = fb.Compile(((BlockExpression)bhex.Body).Expressions, CompilationContext.BindingContext);
var inversion = fb.Compile(((BlockExpression)bhex.Inversion).Expressions, CompilationContext.BindingContext);
var helper = CompilationContext.Configuration.BlockHelpers[bhex.HelperName.Replace("#", "")];
var arguments = new Expression[]
{
Expression.Property(
CompilationContext.BindingContext,
typeof(BindingContext).GetProperty("TextWriter")),
Expression.New(
typeof(HelperOptions).GetConstructors(BindingFlags.Instance | BindingFlags.NonPublic)[0],
body,
inversion),
Expression.Property(
CompilationContext.BindingContext,
typeof(BindingContext).GetProperty("Value")),
Expression.NewArrayInit(typeof(object), bhex.Arguments)
};
if (helper.Target != null)
{
return Expression.Call(
Expression.Constant(helper.Target),
helper.Method,
arguments);
}
else
{
return Expression.Call(
helper.Method,
arguments);
}
}
private Expression GetEnumerableIterator(Expression contextParameter, IteratorExpression iex)
{
var fb = new FunctionBuilder(CompilationContext.Configuration);
return Expression.Block(
Expression.Assign(contextParameter,
Expression.New(
#if netstandard
typeof(IteratorBindingContext).GetTypeInfo().GetConstructor(new[] { typeof(BindingContext) }),
#else
typeof(IteratorBindingContext).GetConstructor(new[] { typeof(BindingContext) }),
#endif
new Expression[] { CompilationContext.BindingContext })),
Expression.Call(
#if netstandard
new Action<IteratorBindingContext, IEnumerable, Action<TextWriter, object>, Action<TextWriter, object>>(Iterate).GetMethodInfo(),
#else
new Action<IteratorBindingContext, IEnumerable, Action<TextWriter, object>, Action<TextWriter, object>>(Iterate).Method,
#endif
new Expression[]
{
Expression.Convert(contextParameter, typeof(IteratorBindingContext)),
Expression.Convert(iex.Sequence, typeof(IEnumerable)),
fb.Compile(new [] { iex.Template }, contextParameter),
fb.Compile(new [] { iex.IfEmpty }, CompilationContext.BindingContext)
}));
}
public HandlebarsCompiler(HandlebarsConfiguration configuration)
{
_configuration=configuration;
_tokenizer = new Tokenizer(configuration);
_expressionBuilder = new ExpressionBuilder(configuration);
_functionBuilder = new FunctionBuilder(configuration);
}
private Expression[] GetDeferredSectionTemplates(DeferredSectionExpression dsex)
{
var fb = new FunctionBuilder(CompilationContext.Configuration);
var body = fb.Compile(dsex.Body.Expressions, CompilationContext.BindingContext);
var inversion = fb.Compile(dsex.Inversion.Expressions, CompilationContext.BindingContext);
var sectionPrefix = dsex.Path.Path.Substring(0, 1);
switch (sectionPrefix)
{
case "#":
return new[] {body, inversion};
case "^":
return new[] {inversion, body};
default:
throw new HandlebarsCompilerException("Tried to compile a section expression that did not begin with # or ^");
}
}
private Expression GetObjectIterator(Expression contextParameter, IteratorExpression iex)
{
var fb = new FunctionBuilder(CompilationContext.Configuration);
return Expression.Block(
Expression.Assign(contextParameter,
Expression.New(
typeof(ObjectEnumeratorBindingContext).GetConstructor(new[] { typeof(BindingContext) }),
new Expression[] { CompilationContext.BindingContext })),
Expression.Call(
new Action<ObjectEnumeratorBindingContext, object, Action<TextWriter, object>, Action<TextWriter, object>>(Iterate).Method,
new Expression[]
{
Expression.Convert(contextParameter, typeof(ObjectEnumeratorBindingContext)),
iex.Sequence,
fb.Compile(new [] { iex.Template }, contextParameter),
fb.Compile(new [] { iex.IfEmpty }, CompilationContext.BindingContext)
}));
}
protected override Expression VisitBlockHelperExpression(BlockHelperExpression bhex)
{
var isInlinePartial = bhex.HelperName == "#*inline";
var context = ExpressionShortcuts.Arg <BindingContext>(CompilationContext.BindingContext);
var bindingContext = isInlinePartial
? context.Cast <object>()
: context.Property(o => o.Value);
var readerContext = ExpressionShortcuts.Arg(bhex.Context);
var body = FunctionBuilder.CompileCore(((BlockExpression)bhex.Body).Expressions, CompilationContext.Configuration);
var inverse = FunctionBuilder.CompileCore(((BlockExpression)bhex.Inversion).Expressions, CompilationContext.Configuration);
var helperName = bhex.HelperName.TrimStart('#', '^');
var textWriter = context.Property(o => o.TextWriter);
var arguments = ExpressionShortcuts.Array <object>(bhex.Arguments.Select(o => FunctionBuilder.Reduce(o, CompilationContext)));
var configuration = ExpressionShortcuts.Arg(CompilationContext.Configuration);
var reducerNew = ExpressionShortcuts.New(() => new LambdaReducer(context, body, inverse));
var reducer = ExpressionShortcuts.Var <LambdaReducer>();
var blockParamsProvider = ExpressionShortcuts.Var <BlockParamsValueProvider>();
var blockParamsExpression = ExpressionShortcuts.Call(
() => BlockParamsValueProvider.Create(context, ExpressionShortcuts.Arg <BlockParam>(bhex.BlockParams))
);
var helperOptions = ExpressionShortcuts.New(
() => new HelperOptions(
reducer.Property(o => o.Direct),
reducer.Property(o => o.Inverse),
blockParamsProvider,
configuration)
);
var blockHelpers = CompilationContext.Configuration.BlockHelpers;
if (blockHelpers.TryGetValue(helperName, out var helper))
{
return(ExpressionShortcuts.Block()
.Parameter(reducer, reducerNew)
.Parameter(blockParamsProvider, blockParamsExpression)
.Line(blockParamsProvider.Using((self, builder) =>
{
builder
.Line(context.Call(o => o.RegisterValueProvider((IValueProvider)self)))
.Line(ExpressionShortcuts.Try()
.Body(ExpressionShortcuts.Call(
() => helper(textWriter, helperOptions, bindingContext, arguments)
))
.Finally(context.Call(o => o.UnregisterValueProvider((IValueProvider)self)))
);
})));
}
foreach (var resolver in CompilationContext.Configuration.HelperResolvers)
{
if (resolver.TryResolveBlockHelper(helperName, out helper))
{
return(ExpressionShortcuts.Block()
.Parameter(reducer, reducerNew)
.Parameter(blockParamsProvider, blockParamsExpression)
.Line(blockParamsProvider.Using((self, builder) =>
{
builder
.Line(context.Call(o => o.RegisterValueProvider((IValueProvider)self)))
.Line(ExpressionShortcuts.Try()
.Body(ExpressionShortcuts.Call(
() => helper(textWriter, helperOptions, bindingContext, arguments)
))
.Finally(context.Call(o => o.UnregisterValueProvider((IValueProvider)self)))
);
})));
}
}
var helperPrefix = bhex.HelperName[0];
return(ExpressionShortcuts.Block()
.Parameter(reducer, reducerNew)
.Parameter(blockParamsProvider, blockParamsExpression)
.Line(blockParamsProvider.Using((self, builder) =>
{
builder
.Line(context.Call(o => o.RegisterValueProvider((IValueProvider)self)))
.Line(ExpressionShortcuts.Try()
.Body(ExpressionShortcuts.Call(
() => LateBoundCall(
helperName,
helperPrefix,
context,
(IReaderContext)readerContext,
textWriter, helperOptions,
body,
inverse,
bindingContext,
self,
arguments
)
))
.Finally(context.Call(o => o.UnregisterValueProvider((IValueProvider)self)))
);
})));
}
protected override Expression VisitBlockHelperExpression(BlockHelperExpression bhex)
{
var isInlinePartial = bhex.HelperName == "#*inline";
var pathInfo = CompilationContext.Configuration.PathInfoStore.GetOrAdd(bhex.HelperName);
var bindingContext = CompilationContext.Args.BindingContext;
var context = isInlinePartial
? bindingContext.As <object>()
: bindingContext.Property(o => o.Value);
var readerContext = bhex.Context;
var direct = Compile(bhex.Body);
var inverse = Compile(bhex.Inversion);
var args = FunctionBinderHelpers.CreateArguments(bhex.Arguments, CompilationContext);
var helperName = pathInfo.TrimmedPath;
var direction = bhex.IsRaw || pathInfo.IsBlockHelper ? BlockHelperDirection.Direct : BlockHelperDirection.Inverse;
var blockParams = CreateBlockParams();
var blockHelpers = CompilationContext.Configuration.BlockHelpers;
if (blockHelpers.TryGetValue(pathInfo, out var descriptor))
{
return(BindByRef(descriptor));
}
var helperResolvers = CompilationContext.Configuration.HelperResolvers;
for (var index = 0; index < helperResolvers.Count; index++)
{
var resolver = helperResolvers[index];
if (!resolver.TryResolveBlockHelper(helperName, out var resolvedDescriptor))
{
continue;
}
descriptor = new StrongBox <BlockHelperDescriptorBase>(resolvedDescriptor);
blockHelpers.Add(pathInfo, descriptor);
return(BindByRef(descriptor));
}
var lateBindBlockHelperDescriptor = new LateBindBlockHelperDescriptor(pathInfo, CompilationContext.Configuration);
var lateBindBlockHelperRef = new StrongBox <BlockHelperDescriptorBase>(lateBindBlockHelperDescriptor);
blockHelpers.Add(pathInfo, lateBindBlockHelperRef);
return(BindByRef(lateBindBlockHelperRef));
ExpressionContainer <ChainSegment[]> CreateBlockParams()
{
var parameters = bhex.BlockParams?.BlockParam?.Parameters;
if (parameters == null)
{
parameters = ArrayEx.Empty <ChainSegment>();
}
return(Arg(parameters));
}
TemplateDelegate Compile(Expression expression)
{
var blockExpression = (BlockExpression)expression;
return(FunctionBuilder.Compile(blockExpression.Expressions, CompilationContext.Configuration));
}
Expression BindByRef(StrongBox <BlockHelperDescriptorBase> helperBox)
{
var writer = CompilationContext.Args.EncodedWriter;
var helperOptions = direction switch
{
BlockHelperDirection.Direct => New(() => new HelperOptions(direct, inverse, blockParams, bindingContext)),
BlockHelperDirection.Inverse => New(() => new HelperOptions(inverse, direct, blockParams, bindingContext)),
_ => throw new HandlebarsCompilerException("Helper referenced with unknown prefix", readerContext)
};
return(Call(() => helperBox.Value.Invoke(writer, helperOptions, context, args)));
}
}
}
protected override Expression VisitBlockHelperExpression(BlockHelperExpression bhex)
{
var isInlinePartial = bhex.HelperName == "#*inline";
var pathInfo = CompilationContext.Configuration.PathInfoStore.GetOrAdd(bhex.HelperName);
var bindingContext = Arg <BindingContext>(CompilationContext.BindingContext);
var context = isInlinePartial
? bindingContext.As <object>()
: bindingContext.Property(o => o.Value);
var readerContext = bhex.Context;
var direct = Compile(bhex.Body);
var inverse = Compile(bhex.Inversion);
var arguments = CreateArguments();
var helperName = pathInfo.TrimmedPath;
var direction = bhex.IsRaw || pathInfo.IsBlockHelper ? BlockHelperDirection.Direct : BlockHelperDirection.Inverse;
var blockParams = CreateBlockParams();
var blockHelpers = CompilationContext.Configuration.BlockHelpers;
if (blockHelpers.TryGetValue(pathInfo, out var descriptor))
{
return(BindByRef(descriptor));
}
var helperResolvers = CompilationContext.Configuration.HelperResolvers;
for (var index = 0; index < helperResolvers.Count; index++)
{
var resolver = helperResolvers[index];
if (!resolver.TryResolveBlockHelper(helperName, out var resolvedDescriptor))
{
continue;
}
return(Bind(resolvedDescriptor));
}
var lateBindBlockHelperDescriptor = new LateBindBlockHelperDescriptor(pathInfo, CompilationContext.Configuration);
var lateBindBlockHelperRef = new StrongBox <BlockHelperDescriptorBase>(lateBindBlockHelperDescriptor);
blockHelpers.Add(pathInfo, lateBindBlockHelperRef);
return(BindByRef(lateBindBlockHelperRef));
ExpressionContainer <ChainSegment[]> CreateBlockParams()
{
var parameters = bhex.BlockParams?.BlockParam?.Parameters;
if (parameters == null)
{
parameters = ArrayEx.Empty <ChainSegment>();
}
return(Arg(parameters));
}
ExpressionContainer <object[]> CreateArguments()
{
var args = bhex.Arguments
.ApplyOn((PathExpression pex) => pex.Context = PathExpression.ResolutionContext.Parameter)
.Select(o => FunctionBuilder.Reduce(o, CompilationContext));
return(Array <object>(args));
}
Action <BindingContext, TextWriter, object> Compile(Expression expression)
{
var blockExpression = (BlockExpression)expression;
return(FunctionBuilder.CompileCore(blockExpression.Expressions, CompilationContext.Configuration));
}
Expression BindByRef(StrongBox <BlockHelperDescriptorBase> value)
{
return(direction switch
{
BlockHelperDirection.Direct => Call(() =>
BlockHelperCallBindingByRef(bindingContext, context, blockParams, direct, inverse, arguments, value)),
BlockHelperDirection.Inverse => Call(() =>
BlockHelperCallBindingByRef(bindingContext, context, blockParams, inverse, direct, arguments, value)),
_ => throw new HandlebarsCompilerException("Helper referenced with unknown prefix", readerContext)
});
