// source returns the full source for the generated state machine.
func (sg *stateGenerator) source(states []*state) esbuilder.SourceBuilder {
if len(states) == 0 {
if sg.isGeneratorFunction {
return esbuilder.Returns(esbuilder.Identifier("$generator").Member("empty").Call())
}
// If there are no states, this is an empty state machine.
return esbuilder.Returns(esbuilder.Identifier("$promise").Member("empty").Call())
}
// Check if this machine is in fact a single state with no jumps. If so, then we don't
// even need the loop and switch.
var singleState *state = nil
if len(states) == 1 && !sg.hasAsyncJump {
singleState = states[0]
}
data := struct {
States []*state
SingleState *state
Snippets snippets
ManagesResources bool
Variables map[string]bool
}{states, singleState, sg.snippets(), sg.managesResources, sg.variables}
if sg.isGeneratorFunction {
return esbuilder.Template("generatorstatemachine", generatorStateMachineTemplateStr, data)
}
return esbuilder.Template("statemachine", stateMachineTemplateStr, data)
}
// generateYield generates the code for a generator yield.
func (sg *stateGenerator) generateYield(yield *codedom.YieldNode) {
if yield.Value != nil {
value := sg.addTopLevelExpression(yield.Value)
templateStr := `
$yield({{ emit .Item }});
`
template := esbuilder.Template("yieldvalue", templateStr, generatingItem{value, sg})
sg.currentState.pushBuilt(sg.addMapping(template, yield))
return
}
if yield.StreamValue != nil {
value := sg.addTopLevelExpression(yield.StreamValue)
templateStr := `
$yieldin({{ emit .Item }});
`
template := esbuilder.Template("yieldin", templateStr, generatingItem{value, sg})
sg.currentState.pushBuilt(sg.addMapping(template, yield))
return
}
templateStr := `
$done();
return;
`
template := esbuilder.Template("yieldbreak", templateStr, generatingItem{yield, sg})
sg.currentState.pushBuilt(sg.addMapping(template, yield))
}
// BuildWrapped returns the builder for this expression. If specified, the expression will be wrapped
// via the given template string. The original expression builder reference will be placed into
// a template field with name "ResultExpr", while any data passed into this method will be placed
// into "Data".
func (er ExpressionResult) BuildWrapped(wrappingTemplateStr string, data interface{}) esbuilder.SourceBuilder {
var result esbuilder.SourceBuilder = er.inlineExpr
// If specified, wrap the expression via the template string.
if wrappingTemplateStr != "" {
fullData := struct {
ResultExpr esbuilder.SourceBuilder
Data interface{}
}{result, data}
result = esbuilder.Template("getbuilder", wrappingTemplateStr, fullData)
}
// For each expression wrapper (in *reverse order*), wrap the result expression via the wrapper.
// This is used to generate promise and other async wrappings.
for rindex, _ := range er.wrappers {
wrapper := er.wrappers[len(er.wrappers)-rindex-1]
templateStr := `({{ emit .PromisingExpression }}).then(function({{ .ResultName }}) {
{{ range $idx, $expr := .IntermediateExpressions }}
{{ emit $expr }};
{{ end }}
{{ if .IsTopLevel }}
{{ emit .WrappedExpression }}
{{ else }}
return ({{ emit .WrappedExpression }});
{{ end }}
})`
data := struct {
// PromisingExpression is the expression of type promise.
PromisingExpression esbuilder.ExpressionBuilder
// ResultName is the name of the result of the promising expression.
ResultName string
// WrappedExpression is the expression being wrapped.
WrappedExpression esbuilder.SourceBuilder
// IsTopLevel returns whether this is the top-level wrapping of the expression.
IsTopLevel bool
// IntermediateExpressions returns the intermediate expression that should be emitted
// before the wrapped expression is invoked.
IntermediateExpressions []esbuilder.ExpressionBuilder
}{wrapper.promisingExpr, wrapper.resultName, result, rindex == 0, wrapper.intermediateExpressions}
result = esbuilder.Template("wrapper", templateStr, data)
}
return result
}
// generateObjectLiteral generates the expression source for a literal object value.
func (eg *expressionGenerator) generateObjectLiteral(objectLiteral *codedom.ObjectLiteralNode, context generationContext) esbuilder.ExpressionBuilder {
// Sort the entries by key to ensure a consistent ordering.
sortedEntries := objectLiteral.Entries
sort.Sort(ByKey(sortedEntries))
// Determine whether we can use the compact form of object literals. The compact form is only
// possible if all the keys are string literals.
var compactFormAllowed = true
entries := make([]interface{}, len(objectLiteral.Entries))
for index, entry := range sortedEntries {
if _, ok := entry.KeyExpression.(*codedom.LiteralValueNode); !ok {
compactFormAllowed = false
}
entries[index] = struct {
Key esbuilder.ExpressionBuilder
Value esbuilder.ExpressionBuilder
}{eg.generateExpression(entry.KeyExpression, context),
eg.generateExpression(entry.ValueExpression, context)}
}
data := struct {
Entries []interface{}
}{entries}
if compactFormAllowed {
templateStr := `
({
{{ range $idx, $entry := .Entries }}
{{ emit $entry.Key }}: {{ emit $entry.Value }},
{{ end }}
})
`
return esbuilder.Template("compactobjectliteral", templateStr, data).AsExpression()
} else {
templateStr := `
((function() {
var obj = {};
{{ range $idx, $entry := .Entries }}
obj[{{ emit $entry.Key }}] = {{ emit $entry.Value }};
{{ end }}
return obj;
})())
`
return esbuilder.Template("expandedobjectliteral", templateStr, data).AsExpression()
}
}
// generateConditionalJump generates the code for a conditional jump.
func (sg *stateGenerator) generateConditionalJump(jump *codedom.ConditionalJumpNode) {
// Add the expression to the state machine. The type will be a nominally-wrapped Boolean, so we need to unwrap it
// here.
expression := sg.addTopLevelExpression(
codedom.NominalUnwrapping(jump.BranchExpression, sg.scopegraph.TypeGraph().BoolTypeReference(), jump.BasisNode()))
currentState := sg.currentState
// Based on the expression value, jump to one state or another.
data := struct {
This codedom.Statement
JumpToTrue string
JumpToFalse string
Expression esbuilder.SourceBuilder
}{jump, sg.jumpToStatement(jump.True), sg.jumpToStatement(jump.False), expression}
templateStr := `
if ({{ emit .Item.Expression }}) {
{{ .Item.JumpToTrue }}
continue;
} else {
{{ .Item.JumpToFalse }}
continue;
}
`
template := esbuilder.Template("conditionaljump", templateStr, generatingItem{data, sg})
currentState.pushBuilt(sg.addMapping(template, jump))
}
// GenerateES5 produces ES5 code from the given scope graph.
func GenerateES5(sg *scopegraph.ScopeGraph, generatedFilePath string, sourceRoot string) (string, *sourcemap.SourceMap, error) {
generated := generateModules(sg)
// Order the modules by their paths.
pather := shared.NewPather(sg.SourceGraph().Graph)
modulePathMap := map[string]esbuilder.SourceBuilder{}
var modulePathList = make([]string, 0)
for module, _ := range generated {
path := pather.GetModulePath(module)
modulePathList = append(modulePathList, path)
modulePathMap[path] = generated[module]
}
sort.Strings(modulePathList)
// Collect the generated modules into their final source.
ordered := ordered_map.NewOrderedMap()
for _, modulePath := range modulePathList {
ordered.Set(modulePath, modulePathMap[modulePath])
}
// Generate the unformatted code and source map.
template := esbuilder.Template("es5", runtimeTemplate, ordered)
sm := sourcemap.NewSourceMap(generatedFilePath, sourceRoot)
unformatted := esbuilder.BuildSourceAndMap(template, sm)
// Format the code.
return escommon.FormatMappedECMASource(unformatted.String(), sm)
}
// Source returns the full source for this state.
func (s *state) SourceTemplate() esbuilder.SourceBuilder {
templateStr := `{{ range $piece := .Pieces }}
{{ emit $piece }}
{{ end }}`
return esbuilder.Template("state", templateStr, s)
}
// generateRejection generates the code for promise rejection.
func (sg *stateGenerator) generateRejection(rejection *codedom.RejectionNode) {
value := sg.addTopLevelExpression(rejection.Value)
templateStr := `
$reject({{ emit .Item }});
return;
`
template := esbuilder.Template("rejection", templateStr, generatingItem{value, sg})
sg.currentState.pushBuilt(sg.addMapping(template, rejection))
}
// addTopLevelExpression generates the source for the given expression and adds it to the
// state machine.
func (sg *stateGenerator) addTopLevelExpression(expression codedom.Expression) esbuilder.SourceBuilder {
// Generate the expression.
result := expressiongenerator.GenerateExpression(expression, expressiongenerator.AllowedSync,
sg.scopegraph, sg.positionMapper,
sg.generateMachine)
// Add any variables generated by the expression.
for _, varName := range result.Variables() {
sg.addVariable(varName)
}
// If the expression generated is asynchronous, then it will have at least one
// promise callback. In order to ensure continued execution, we have to wrap
// the resulting expression in a jump to a new state once it has finished executing.
if result.IsAsync() {
// Add $result, as it is needed below.
sg.addVariable("$result")
sg.hasAsyncJump = true
// Save the current state and create a new state to jump to once the expression's
// promise has resolved.
currentState := sg.currentState
targetState := sg.newState()
// Wrap the expression's promise result expression to be stored in $result,
// followed by a jump to the new state.
data := struct {
ResolutionStateId stateId
Snippets snippets
IsGenerator bool
}{targetState.ID, sg.snippets(), sg.isGeneratorFunction}
wrappingTemplateStr := `
$result = {{ emit .ResultExpr }};
{{ .Data.Snippets.SetState .Data.ResolutionStateId }}
{{ .Data.Snippets.Continue .Data.IsGenerator }}
`
promise := result.BuildWrapped(wrappingTemplateStr, data)
// Wrap the expression's promise with a catch, in case it fails.
catchTemplateStr := `
({{ emit .Item }}).catch(function(err) {
{{ .Snippets.Reject "err" }}
});
return;
`
currentState.pushBuilt(esbuilder.Template("tlecatch", catchTemplateStr, generatingItem{promise, sg}))
return esbuilder.Identifier("$result")
} else {
// Otherwise, the expression is synchronous and we can just invoke it.
return result.Build()
}
}
// generateImplementedMember generates the given member into ES5.
func (gen *es5generator) generateImplementedMember(member typegraph.TGMember) esbuilder.SourceBuilder {
srgMember, _ := gen.getSRGMember(member)
generating := generatingMember{member, srgMember, gen}
switch srgMember.MemberKind() {
case srg.ConstructorMember:
fallthrough
case srg.FunctionMember:
fallthrough
case srg.OperatorMember:
return esbuilder.Template("function", functionTemplateStr, generating)
case srg.PropertyMember:
return esbuilder.Template("property", propertyTemplateStr, generating)
default:
panic(fmt.Sprintf("Unknown kind of member %s", srgMember.MemberKind()))
}
}
// Set sets the given key to the given value. Note that the value *must* be a generatedSourceResult,
// but this function takes in an interface{} to match the interface of the normal OrderedMap.
func (gim *generatedInitMap) Set(key interface{}, value interface{}) {
result := value.(generatedSourceResult)
if result.IsPromise {
gim.promising = true
wrappedSource := esbuilder.Template("wrappedinit", `
(init.push({{ emit . }}))
`, result.Source)
gim.orderedMap.Set(key, wrappedSource)
} else {
gim.orderedMap.Set(key, result.Source)
}
}
// generateType generates the given type into ES5.
func (gen *es5generator) generateType(typedef typegraph.TGTypeDecl) esbuilder.SourceBuilder {
generating := generatingType{typedef, gen}
switch typedef.TypeKind() {
case typegraph.ClassType:
return esbuilder.Template("class", classTemplateStr, generating)
case typegraph.ImplicitInterfaceType:
return esbuilder.Template("interface", interfaceTemplateStr, generating)
case typegraph.NominalType:
return esbuilder.Template("nominal", nominalTemplateStr, generating)
case typegraph.StructType:
return esbuilder.Template("struct", structTemplateStr, generating)
case typegraph.ExternalInternalType:
return esbuilder.Snippet("")
default:
panic("Unknown typedef kind")
}
}
// generateUnconditionalJump generates the code for an unconditional jump.
func (sg *stateGenerator) generateUnconditionalJump(jump *codedom.UnconditionalJumpNode) {
currentState := sg.currentState
data := struct {
JumpToTarget string
}{sg.jumpToStatement(jump.Target)}
templateStr := `
{{ .Item.JumpToTarget }}
continue;
`
template := esbuilder.Template("unconditionaljump", templateStr, generatingItem{data, sg})
currentState.pushBuilt(sg.addMapping(template, jump))
}
// generateArrowPromise generates the code for an arrow promise.
func (sg *stateGenerator) generateArrowPromise(arrowPromise *codedom.ArrowPromiseNode) {
currentState := sg.currentState
sg.generateStates(arrowPromise.Target, generateNewState)
childExpression := sg.addTopLevelExpression(arrowPromise.ChildExpression)
var resolutionAssignment esbuilder.SourceBuilder = nil
var rejectionAssignment esbuilder.SourceBuilder = nil
if arrowPromise.ResolutionAssignment != nil {
resolutionAssignment = sg.addTopLevelExpression(arrowPromise.ResolutionAssignment)
}
if arrowPromise.RejectionAssignment != nil {
rejectionAssignment = sg.addTopLevelExpression(arrowPromise.RejectionAssignment)
}
data := struct {
JumpToTarget string
ChildExpression esbuilder.SourceBuilder
ResolutionAssignment esbuilder.SourceBuilder
RejectionAssignment esbuilder.SourceBuilder
}{sg.jumpToStatement(arrowPromise.Target), childExpression, resolutionAssignment, rejectionAssignment}
templateStr := `
({{ emit .Item.ChildExpression }}).then(function(resolved) {
{{ if .Item.ResolutionAssignment }}
{{ emit .Item.ResolutionAssignment }}
{{ end }}
{{ .Item.JumpToTarget }}
{{ .Snippets.Continue .IsGenerator }}
}).catch(function(rejected) {
{{ if .Item.RejectionAssignment }}
{{ emit .Item.RejectionAssignment }}
{{ .Item.JumpToTarget }}
{{ .Snippets.Continue .IsGenerator }}
{{ else }}
{{ .Snippets.Reject "rejected" }}
{{ end }}
});
return;
`
template := esbuilder.Template("arrowpromise", templateStr, generatingItem{data, sg})
currentState.pushBuilt(sg.addMapping(template, arrowPromise))
}
// generateVarDefinition generates the code for a variable definition.
func (sg *stateGenerator) generateVarDefinition(vardef *codedom.VarDefinitionNode) {
sg.addVariable(vardef.Name)
if vardef.Initializer != nil {
data := struct {
Name string
Initializer esbuilder.SourceBuilder
}{vardef.Name, sg.addTopLevelExpression(vardef.Initializer)}
templateStr := `
{{ .Item.Name }} = {{ emit .Item.Initializer }};
`
template := esbuilder.Template("vardef", templateStr, generatingItem{data, sg})
sg.currentState.pushBuilt(sg.addMapping(template, vardef))
}
}
// generateFunctionDefinition generates the code for a function.
func (eg *expressionGenerator) generateFunctionDefinition(function *codedom.FunctionDefinitionNode, context generationContext) esbuilder.ExpressionBuilder {
templateStr := `
{{ if .Item.WorkerExecute }}
$t.workerwrap('{{ .Item.UniqueId }}',
{{ end }}
({{ if .Item.Generics }}
function({{ range $index, $generic := .Item.Generics }}{{ if $index }}, {{ end }}{{ $generic }}{{ end }}) {
{{ if .Item.RequiresThis }}var $this = this;{{ end }}
var $f =
{{ end }}
function({{ range $index, $parameter := .Item.Parameters }}{{ if $index }}, {{ end }}{{ $parameter }}{{ end }}) {
{{ if not .Item.Generics }}{{ if .Item.RequiresThis }}var $this = this;{{ end }}{{ end }}
{{ $body := .GeneratedBody }}
{{ if .Item.IsGenerator }}
{{ if $body }}
{{ emit $body }}
return $generator.new($continue);
{{ else }}
return $generator.empty();
{{ end }}
{{ else }}
{{ if $body }}
{{ emit $body }}
return $promise.new($continue);
{{ else }}
return $promise.empty();
{{ end }}
{{ end }}
}
{{ if .Item.Generics }}
return $f;
}
{{ end }})
{{ if .Item.WorkerExecute }}
)
{{ end }}
`
data := struct {
Item *codedom.FunctionDefinitionNode
GeneratedBody esbuilder.SourceBuilder
}{function, eg.machineBuilder(function.Body, function.IsGenerator())}
return esbuilder.Template("functiondef", templateStr, data).AsExpression()
}
// generateResolution generates the code for promise resolution.
func (sg *stateGenerator) generateResolution(resolution *codedom.ResolutionNode) {
var value esbuilder.SourceBuilder = nil
if resolution.Value != nil {
value = sg.addTopLevelExpression(resolution.Value)
}
templateStr := `
{{ if .Item }}
$resolve({{ emit .Item }});
return;
{{ else }}
{{ .Snippets.Resolve "" }}
{{ end }}
`
template := esbuilder.Template("resolution", templateStr, generatingItem{value, sg})
sg.currentState.pushBuilt(sg.addMapping(template, resolution))
}
// generateVariable generates the given variable into ES5.
func (gen *es5generator) generateVariable(member typegraph.TGMember) generatedSourceResult {
srgMember, _ := gen.getSRGMember(member)
initializer, _ := srgMember.Initializer()
initResult := statemachine.GenerateExpressionResult(initializer, gen.scopegraph, gen.positionMapper)
prefix := "instance"
if member.IsStatic() {
prefix = "$static"
}
data := struct {
Name string
Prefix string
Initializer expressiongenerator.ExpressionResult
}{member.Name(), prefix, initResult}
source := esbuilder.Template("variable", variableTemplateStr, data)
return generatedSourceResult{source, initResult.IsPromise()}
}
// GenerateComposition generates the source for all the composed types structurually inherited by the type.
func (gt generatingType) GenerateComposition() *generatedInitMap {
initMap := newGeneratedInitMap()
parentTypes := gt.Type.ParentTypes()
for _, parentTypeRef := range parentTypes {
data := struct {
ComposedTypeLocation string
InnerInstanceName string
RequiredFields []typegraph.TGMember
}{
gt.Generator.pather.TypeReferenceCall(parentTypeRef),
gt.Generator.pather.InnerInstanceName(parentTypeRef),
parentTypeRef.ReferredType().RequiredFields(),
}
source := esbuilder.Template("composition", compositionTemplateStr, data)
initMap.Set(parentTypeRef, generatedSourceResult{source, true})
}
return initMap
}
// generateModule generates the given module into ES5.
func (gen *es5generator) generateModule(module typegraph.TGModule) esbuilder.SourceBuilder {
generating := generatingModule{module, gen}
return esbuilder.Template("module", moduleTemplateStr, generating)
}
// generateImplementedAliasedMember generates the given member into an alias in ES5.
func (gen *es5generator) generateImplementedAliasedMember(member typegraph.TGMember) esbuilder.SourceBuilder {
srgMember, _ := gen.getSRGMember(member)
generating := generatingMember{member, srgMember, gen}
return esbuilder.Template("aliasedmember", aliasedMemberTemplateStr, generating)
}
// generateResolveExpression generates the code for an expression resolution.
func (sg *stateGenerator) generateResolveExpression(resolveExpression *codedom.ResolveExpressionNode) {
// Generate the resolved expression, requiring that it is asynchronous to ensure it becomes
// a Promise.
result := expressiongenerator.GenerateExpression(resolveExpression.ChildExpression,
expressiongenerator.EnsureAsync,
sg.scopegraph, sg.positionMapper,
sg.generateMachine)
var resolutionName = ""
var rejectionName = ""
if resolveExpression.ResolutionName != "" {
resolutionName = sg.addVariable(resolveExpression.ResolutionName)
}
if resolveExpression.RejectionName != "" {
rejectionName = sg.addVariable(resolveExpression.RejectionName)
}
// Save the current state and create a new state to jump to once the expression's
// promise has resolved or rejected.
currentState := sg.currentState
sg.generateStates(resolveExpression.Target, generateNewState)
// Build the expression with an assignment of the resolved expression value assigned to
// the resolution variable (if any) and then a jump to the post-resolution state.
jumpToTarget := sg.jumpToStatement(resolveExpression.Target)
resolveData := struct {
ResolutionName string
RejectionName string
JumpToTarget string
Snippets snippets
IsGenerator bool
}{resolutionName, rejectionName, jumpToTarget, sg.snippets(), sg.isGeneratorFunction}
wrappingTemplateStr := `
{{ if .Data.ResolutionName }}
{{ .Data.ResolutionName }} = {{ emit .ResultExpr }};
{{ end }}
{{ if .Data.RejectionName }}
{{ .Data.RejectionName }} = null;
{{ end }}
{{ .Data.JumpToTarget }}
{{ .Data.Snippets.Continue .Data.IsGenerator }}
`
promise := result.BuildWrapped(wrappingTemplateStr, resolveData)
// Similarly, add a .catch onto the Promise with an assignment of the rejected error (if any)
// to the rejection variable (if any) and then a jump to the post-rejection state.
rejectData := struct {
Promise esbuilder.SourceBuilder
ResolutionName string
RejectionName string
JumpToTarget string
Snippets snippets
IsGenerator bool
}{promise, resolutionName, rejectionName, jumpToTarget, sg.snippets(), sg.isGeneratorFunction}
catchTemplateStr := `
({{ emit .Promise }}).catch(function($rejected) {
{{ if .RejectionName }}
{{ .RejectionName }} = $rejected;
{{ end }}
{{ if .ResolutionName }}
{{ .ResolutionName }} = null;
{{ end }}
{{ .JumpToTarget }}
{{ .Snippets.Continue .IsGenerator }}
});
return;
`
currentState.pushBuilt(esbuilder.Template("resolvecatch", catchTemplateStr, rejectData))
}