Package com.google.javascript.jscomp.parsing.parser

Class FeatureSet

java.lang.Object

com.google.javascript.jscomp.parsing.parser.FeatureSet

All Implemented Interfaces:

java.io.Serializable

@Immutable
public final class FeatureSet
extends java.lang.Object
implements java.io.Serializable

Represents various aspects of language version and support.

This is somewhat redundant with LanguageMode, but is separate for two reasons: (1) it's used for parsing, which cannot depend on LanguageMode, and (2) it's concerned with slightly different nuances: implemented features and modules rather than strictness.

In the long term, it would be good to disentangle all these concerns and pull out a single LanguageSyntax enum with a separate strict mode flag, and then these could possibly be unified.

Instances of this class are immutable.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	FeatureSet.Feature	Specific features that can be included in a FeatureSet.

Field Summary

Fields

Modifier and Type	Field	Description
static FeatureSet	ALL
static FeatureSet	BARE_MINIMUM	The bare minimum set of features.
static FeatureSet	BROWSER_2020
static FeatureSet	BROWSER_2021
static FeatureSet	BROWSER_2022
static FeatureSet	ES_NEXT
static FeatureSet	ES_UNSTABLE
static FeatureSet	ES_UNSUPPORTED
static FeatureSet	ES2015	The full set of ES2015 features, not including modules.
static FeatureSet	ES2015_MODULES	All ES2015 features, including modules.
static FeatureSet	ES2016
static FeatureSet	ES2016_MODULES
static FeatureSet	ES2017
static FeatureSet	ES2017_MODULES
static FeatureSet	ES2018
static FeatureSet	ES2018_MODULES
static FeatureSet	ES2019
static FeatureSet	ES2019_MODULES
static FeatureSet	ES2020
static FeatureSet	ES2020_MODULES
static FeatureSet	ES2021
static FeatureSet	ES2021_MODULES
static FeatureSet	ES3	Features from ES3.
static FeatureSet	ES5	Features from ES5 only.

Method Summary

Modifier and Type	Method	Description
static FeatureSet	all()	Returns a FeatureSet containing all known features.
boolean	contains(FeatureSet other)	Does this FeatureSet contain all of the features of other?
boolean	contains(FeatureSet.Feature feature)	Does this FeatureSet contain the given feature?
boolean	containsAtLeastOneOf(FeatureSet other)	Does this FeatureSet contain at least one of the features of other?
boolean	equals(java.lang.Object other)
com.google.common.collect.ImmutableSet<FeatureSet.Feature>	getFeatures()
boolean	has(FeatureSet.Feature feature)	Does this FeatureSet include feature?
int	hashCode()
static FeatureSet	latest()
java.lang.String	toString()
FeatureSet	union(FeatureSet other)	Returns a new FeatureSet including all features of both this and other.
static FeatureSet	valueOf(java.lang.String name)	Parses known strings into feature sets.
java.lang.String	version()	Returns a string representation suitable for use in polyfill definition files and encoding in depgraph and deps.js files.
java.lang.String	versionForDebugging()	Deprecated. Please use version() instead.
FeatureSet	with(FeatureSet newFeatures)	Returns a feature set combining all the features from this and newFeatures.
FeatureSet	with(FeatureSet.Feature feature)	Returns a feature set combining all the features from this and feature.
FeatureSet	with(FeatureSet.Feature... newFeatures)	Returns a feature set combining all the features from this and newFeatures.
FeatureSet	with(java.util.Set<FeatureSet.Feature> newFeatures)	Returns a feature set combining all the features from this and newFeatures.
FeatureSet	without(FeatureSet other)
FeatureSet	without(FeatureSet.Feature featureToRemove, FeatureSet.Feature... moreFeaturesToRemove)
FeatureSet	withoutTypes()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

BARE_MINIMUM

public static final FeatureSet BARE_MINIMUM

The bare minimum set of features.

ES3

public static final FeatureSet ES3

Features from ES3.

ES5

public static final FeatureSet ES5

Features from ES5 only.

ES2015_MODULES

public static final FeatureSet ES2015_MODULES

All ES2015 features, including modules.

ES2015

public static final FeatureSet ES2015

The full set of ES2015 features, not including modules.

ES2016_MODULES

public static final FeatureSet ES2016_MODULES

ES2016

public static final FeatureSet ES2016

ES2017_MODULES

public static final FeatureSet ES2017_MODULES

ES2017

public static final FeatureSet ES2017

ES2018_MODULES

public static final FeatureSet ES2018_MODULES

ES2018

public static final FeatureSet ES2018

ES2019_MODULES

public static final FeatureSet ES2019_MODULES

ES2019

public static final FeatureSet ES2019

ES2020_MODULES

public static final FeatureSet ES2020_MODULES

ES2020

public static final FeatureSet ES2020

ES2021_MODULES

public static final FeatureSet ES2021_MODULES

ES2021

public static final FeatureSet ES2021

ES_NEXT

public static final FeatureSet ES_NEXT

ES_UNSTABLE

public static final FeatureSet ES_UNSTABLE

ES_UNSUPPORTED

public static final FeatureSet ES_UNSUPPORTED

BROWSER_2020

public static final FeatureSet BROWSER_2020

BROWSER_2021

public static final FeatureSet BROWSER_2021

BROWSER_2022

public static final FeatureSet BROWSER_2022

ALL

public static final FeatureSet ALL

Method Detail

version

public java.lang.String version()

Returns a string representation suitable for use in polyfill definition files and encoding in depgraph and deps.js files.

versionForDebugging

@Deprecated
public java.lang.String versionForDebugging()

Deprecated.

Please use version() instead.

Returns a string representation useful for debugging.

without

public FeatureSet without(FeatureSet.Feature featureToRemove,
                          FeatureSet.Feature... moreFeaturesToRemove)

without

public FeatureSet without(FeatureSet other)

withoutTypes

public FeatureSet withoutTypes()

union

public FeatureSet union(FeatureSet other)

Returns a new FeatureSet including all features of both this and other.

containsAtLeastOneOf

public boolean containsAtLeastOneOf(FeatureSet other)

Does this FeatureSet contain at least one of the features of other?

contains

public boolean contains(FeatureSet other)

Does this FeatureSet contain all of the features of other?

contains

public boolean contains(FeatureSet.Feature feature)

Does this FeatureSet contain the given feature?

with

public FeatureSet with(FeatureSet.Feature feature)

Returns a feature set combining all the features from this and feature.

with

public FeatureSet with(FeatureSet.Feature... newFeatures)

Returns a feature set combining all the features from this and newFeatures.

with

public FeatureSet with(java.util.Set<FeatureSet.Feature> newFeatures)

Returns a feature set combining all the features from this and newFeatures.

with

public FeatureSet with(FeatureSet newFeatures)

Returns a feature set combining all the features from this and newFeatures.

has

public boolean has(FeatureSet.Feature feature)

Does this FeatureSet include feature?

getFeatures

public com.google.common.collect.ImmutableSet<FeatureSet.Feature> getFeatures()

equals

public boolean equals(java.lang.Object other)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

valueOf

public static FeatureSet valueOf(java.lang.String name)

Parses known strings into feature sets.

all

public static FeatureSet all()

Returns a FeatureSet containing all known features.

NOTE: PassFactory classes that claim to support FeatureSet.all() should be only those that cannot be broken by new features being added to the language. Mainly these are passes that don't have to actually look at the AST at all, like empty marker passes.

latest

public static FeatureSet latest()