Source: globals.go in package github.com/evanw/esbuild/internal/config

package config

import (
	"math"
	"strings"
	"sync"

	"github.com/evanw/esbuild/internal/js_ast"
	"github.com/evanw/esbuild/internal/logger"
)

var processedGlobalsMutex sync.Mutex
var processedGlobals *ProcessedDefines

If something is in this list, then a direct identifier expression or property access chain matching this will be assumed to have no side effects and will be removed. This also means code is allowed to be reordered past things in this list. For example, if "console.log" is in this list, permitting reordering allows for "if (a) console.log(b); else console.log(c)" to be reordered and transformed into "console.log(a ? b : c)". Notice that "a" and "console.log" are in a different order, which can only happen if evaluating the "console.log" property access can be assumed to not change the value of "a". Note that membership in this list says nothing about whether calling any of these functions has any side effects. It only says something about referencing these function without calling them.

These global identifiers should exist in all JavaScript environments. This deliberately omits "NaN", "Infinity", and "undefined" because these are treated as automatically-inlined constants instead of identifiers.

	{"Array"},
	{"Boolean"},
	{"Function"},
	{"Math"},
	{"Number"},
	{"Object"},
	{"RegExp"},
	{"String"},

Object: Static methods https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object#Static_methods

	{"Object", "assign"},
	{"Object", "create"},
	{"Object", "defineProperties"},
	{"Object", "defineProperty"},
	{"Object", "entries"},
	{"Object", "freeze"},
	{"Object", "fromEntries"},
	{"Object", "getOwnPropertyDescriptor"},
	{"Object", "getOwnPropertyDescriptors"},
	{"Object", "getOwnPropertyNames"},
	{"Object", "getOwnPropertySymbols"},
	{"Object", "getPrototypeOf"},
	{"Object", "is"},
	{"Object", "isExtensible"},
	{"Object", "isFrozen"},
	{"Object", "isSealed"},
	{"Object", "keys"},
	{"Object", "preventExtensions"},
	{"Object", "seal"},
	{"Object", "setPrototypeOf"},
	{"Object", "values"},

Object: Instance methods https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object#Instance_methods

	{"Object", "prototype", "__defineGetter__"},
	{"Object", "prototype", "__defineSetter__"},
	{"Object", "prototype", "__lookupGetter__"},
	{"Object", "prototype", "__lookupSetter__"},
	{"Object", "prototype", "hasOwnProperty"},
	{"Object", "prototype", "isPrototypeOf"},
	{"Object", "prototype", "propertyIsEnumerable"},
	{"Object", "prototype", "toLocaleString"},
	{"Object", "prototype", "toString"},
	{"Object", "prototype", "unwatch"},
	{"Object", "prototype", "valueOf"},
	{"Object", "prototype", "watch"},

Math: Static properties https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math#Static_properties

	{"Math", "E"},
	{"Math", "LN10"},
	{"Math", "LN2"},
	{"Math", "LOG10E"},
	{"Math", "LOG2E"},
	{"Math", "PI"},
	{"Math", "SQRT1_2"},
	{"Math", "SQRT2"},

Math: Static methods https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math#Static_methods

	{"Math", "abs"},
	{"Math", "acos"},
	{"Math", "acosh"},
	{"Math", "asin"},
	{"Math", "asinh"},
	{"Math", "atan"},
	{"Math", "atan2"},
	{"Math", "atanh"},
	{"Math", "cbrt"},
	{"Math", "ceil"},
	{"Math", "clz32"},
	{"Math", "cos"},
	{"Math", "cosh"},
	{"Math", "exp"},
	{"Math", "expm1"},
	{"Math", "floor"},
	{"Math", "fround"},
	{"Math", "hypot"},
	{"Math", "imul"},
	{"Math", "log"},
	{"Math", "log10"},
	{"Math", "log1p"},
	{"Math", "log2"},
	{"Math", "max"},
	{"Math", "min"},
	{"Math", "pow"},
	{"Math", "random"},
	{"Math", "round"},
	{"Math", "sign"},
	{"Math", "sin"},
	{"Math", "sinh"},
	{"Math", "sqrt"},
	{"Math", "tan"},
	{"Math", "tanh"},
	{"Math", "trunc"},

Other globals present in both the browser and node (except "eval" because it has special behavior)

	{"AbortController"},
	{"AbortSignal"},
	{"AggregateError"},
	{"ArrayBuffer"},
	{"BigInt"},
	{"DataView"},
	{"Date"},
	{"Error"},
	{"EvalError"},
	{"Event"},
	{"EventTarget"},
	{"Float32Array"},
	{"Float64Array"},
	{"Int16Array"},
	{"Int32Array"},
	{"Int8Array"},
	{"Intl"},
	{"JSON"},
	{"Map"},
	{"MessageChannel"},
	{"MessageEvent"},
	{"MessagePort"},
	{"Promise"},
	{"Proxy"},
	{"RangeError"},
	{"ReferenceError"},
	{"Reflect"},
	{"Set"},
	{"Symbol"},
	{"SyntaxError"},
	{"TextDecoder"},
	{"TextEncoder"},
	{"TypeError"},
	{"URIError"},
	{"URL"},
	{"URLSearchParams"},
	{"Uint16Array"},
	{"Uint32Array"},
	{"Uint8Array"},
	{"Uint8ClampedArray"},
	{"WeakMap"},
	{"WeakSet"},
	{"WebAssembly"},
	{"clearInterval"},
	{"clearTimeout"},
	{"console"},
	{"decodeURI"},
	{"decodeURIComponent"},
	{"encodeURI"},
	{"encodeURIComponent"},
	{"escape"},
	{"globalThis"},
	{"isFinite"},
	{"isNaN"},
	{"parseFloat"},
	{"parseInt"},
	{"queueMicrotask"},
	{"setInterval"},
	{"setTimeout"},
	{"unescape"},

Console method references are assumed to have no side effects https://developer.mozilla.org/en-US/docs/Web/API/console

	{"console", "assert"},
	{"console", "clear"},
	{"console", "count"},
	{"console", "countReset"},
	{"console", "debug"},
	{"console", "dir"},
	{"console", "dirxml"},
	{"console", "error"},
	{"console", "group"},
	{"console", "groupCollapsed"},
	{"console", "groupEnd"},
	{"console", "info"},
	{"console", "log"},
	{"console", "table"},
	{"console", "time"},
	{"console", "timeEnd"},
	{"console", "timeLog"},
	{"console", "trace"},
	{"console", "warn"},

CSSOM APIs

	{"CSSAnimation"},
	{"CSSFontFaceRule"},
	{"CSSImportRule"},
	{"CSSKeyframeRule"},
	{"CSSKeyframesRule"},
	{"CSSMediaRule"},
	{"CSSNamespaceRule"},
	{"CSSPageRule"},
	{"CSSRule"},
	{"CSSRuleList"},
	{"CSSStyleDeclaration"},
	{"CSSStyleRule"},
	{"CSSStyleSheet"},
	{"CSSSupportsRule"},
	{"CSSTransition"},

SVG DOM

	{"SVGAElement"},
	{"SVGAngle"},
	{"SVGAnimateElement"},
	{"SVGAnimateMotionElement"},
	{"SVGAnimateTransformElement"},
	{"SVGAnimatedAngle"},
	{"SVGAnimatedBoolean"},
	{"SVGAnimatedEnumeration"},
	{"SVGAnimatedInteger"},
	{"SVGAnimatedLength"},
	{"SVGAnimatedLengthList"},
	{"SVGAnimatedNumber"},
	{"SVGAnimatedNumberList"},
	{"SVGAnimatedPreserveAspectRatio"},
	{"SVGAnimatedRect"},
	{"SVGAnimatedString"},
	{"SVGAnimatedTransformList"},
	{"SVGAnimationElement"},
	{"SVGCircleElement"},
	{"SVGClipPathElement"},
	{"SVGComponentTransferFunctionElement"},
	{"SVGDefsElement"},
	{"SVGDescElement"},
	{"SVGElement"},
	{"SVGEllipseElement"},
	{"SVGFEBlendElement"},
	{"SVGFEColorMatrixElement"},
	{"SVGFEComponentTransferElement"},
	{"SVGFECompositeElement"},
	{"SVGFEConvolveMatrixElement"},
	{"SVGFEDiffuseLightingElement"},
	{"SVGFEDisplacementMapElement"},
	{"SVGFEDistantLightElement"},
	{"SVGFEDropShadowElement"},
	{"SVGFEFloodElement"},
	{"SVGFEFuncAElement"},
	{"SVGFEFuncBElement"},
	{"SVGFEFuncGElement"},
	{"SVGFEFuncRElement"},
	{"SVGFEGaussianBlurElement"},
	{"SVGFEImageElement"},
	{"SVGFEMergeElement"},
	{"SVGFEMergeNodeElement"},
	{"SVGFEMorphologyElement"},
	{"SVGFEOffsetElement"},
	{"SVGFEPointLightElement"},
	{"SVGFESpecularLightingElement"},
	{"SVGFESpotLightElement"},
	{"SVGFETileElement"},
	{"SVGFETurbulenceElement"},
	{"SVGFilterElement"},
	{"SVGForeignObjectElement"},
	{"SVGGElement"},
	{"SVGGeometryElement"},
	{"SVGGradientElement"},
	{"SVGGraphicsElement"},
	{"SVGImageElement"},
	{"SVGLength"},
	{"SVGLengthList"},
	{"SVGLineElement"},
	{"SVGLinearGradientElement"},
	{"SVGMPathElement"},
	{"SVGMarkerElement"},
	{"SVGMaskElement"},
	{"SVGMatrix"},
	{"SVGMetadataElement"},
	{"SVGNumber"},
	{"SVGNumberList"},
	{"SVGPathElement"},
	{"SVGPatternElement"},
	{"SVGPoint"},
	{"SVGPointList"},
	{"SVGPolygonElement"},
	{"SVGPolylineElement"},
	{"SVGPreserveAspectRatio"},
	{"SVGRadialGradientElement"},
	{"SVGRect"},
	{"SVGRectElement"},
	{"SVGSVGElement"},
	{"SVGScriptElement"},
	{"SVGSetElement"},
	{"SVGStopElement"},
	{"SVGStringList"},
	{"SVGStyleElement"},
	{"SVGSwitchElement"},
	{"SVGSymbolElement"},
	{"SVGTSpanElement"},
	{"SVGTextContentElement"},
	{"SVGTextElement"},
	{"SVGTextPathElement"},
	{"SVGTextPositioningElement"},
	{"SVGTitleElement"},
	{"SVGTransform"},
	{"SVGTransformList"},
	{"SVGUnitTypes"},
	{"SVGUseElement"},
	{"SVGViewElement"},

Other browser APIs This list contains all globals present in modern versions of Chrome, Safari, and Firefox except for the following properties, since they have a side effect of triggering layout (https://gist.github.com/paulirish/5d52fb081b3570c81e3a): - scrollX - scrollY - innerWidth - innerHeight - pageXOffset - pageYOffset The following globals have also been removed since they sometimes throw an exception when accessed, which is a side effect (for more information see https://stackoverflow.com/a/33047477): - localStorage - sessionStorage

	{"AnalyserNode"},
	{"Animation"},
	{"AnimationEffect"},
	{"AnimationEvent"},
	{"AnimationPlaybackEvent"},
	{"AnimationTimeline"},
	{"Attr"},
	{"Audio"},
	{"AudioBuffer"},
	{"AudioBufferSourceNode"},
	{"AudioDestinationNode"},
	{"AudioListener"},
	{"AudioNode"},
	{"AudioParam"},
	{"AudioProcessingEvent"},
	{"AudioScheduledSourceNode"},
	{"BarProp"},
	{"BeforeUnloadEvent"},
	{"BiquadFilterNode"},
	{"Blob"},
	{"BlobEvent"},
	{"ByteLengthQueuingStrategy"},
	{"CDATASection"},
	{"CSS"},
	{"CanvasGradient"},
	{"CanvasPattern"},
	{"CanvasRenderingContext2D"},
	{"ChannelMergerNode"},
	{"ChannelSplitterNode"},
	{"CharacterData"},
	{"ClipboardEvent"},
	{"CloseEvent"},
	{"Comment"},
	{"CompositionEvent"},
	{"ConvolverNode"},
	{"CountQueuingStrategy"},
	{"Crypto"},
	{"CustomElementRegistry"},
	{"CustomEvent"},
	{"DOMException"},
	{"DOMImplementation"},
	{"DOMMatrix"},
	{"DOMMatrixReadOnly"},
	{"DOMParser"},
	{"DOMPoint"},
	{"DOMPointReadOnly"},
	{"DOMQuad"},
	{"DOMRect"},
	{"DOMRectList"},
	{"DOMRectReadOnly"},
	{"DOMStringList"},
	{"DOMStringMap"},
	{"DOMTokenList"},
	{"DataTransfer"},
	{"DataTransferItem"},
	{"DataTransferItemList"},
	{"DelayNode"},
	{"Document"},
	{"DocumentFragment"},
	{"DocumentTimeline"},
	{"DocumentType"},
	{"DragEvent"},
	{"DynamicsCompressorNode"},
	{"Element"},
	{"ErrorEvent"},
	{"EventSource"},
	{"File"},
	{"FileList"},
	{"FileReader"},
	{"FocusEvent"},
	{"FontFace"},
	{"FormData"},
	{"GainNode"},
	{"Gamepad"},
	{"GamepadButton"},
	{"GamepadEvent"},
	{"Geolocation"},
	{"GeolocationPositionError"},
	{"HTMLAllCollection"},
	{"HTMLAnchorElement"},
	{"HTMLAreaElement"},
	{"HTMLAudioElement"},
	{"HTMLBRElement"},
	{"HTMLBaseElement"},
	{"HTMLBodyElement"},
	{"HTMLButtonElement"},
	{"HTMLCanvasElement"},
	{"HTMLCollection"},
	{"HTMLDListElement"},
	{"HTMLDataElement"},
	{"HTMLDataListElement"},
	{"HTMLDetailsElement"},
	{"HTMLDirectoryElement"},
	{"HTMLDivElement"},
	{"HTMLDocument"},
	{"HTMLElement"},
	{"HTMLEmbedElement"},
	{"HTMLFieldSetElement"},
	{"HTMLFontElement"},
	{"HTMLFormControlsCollection"},
	{"HTMLFormElement"},
	{"HTMLFrameElement"},
	{"HTMLFrameSetElement"},
	{"HTMLHRElement"},
	{"HTMLHeadElement"},
	{"HTMLHeadingElement"},
	{"HTMLHtmlElement"},
	{"HTMLIFrameElement"},
	{"HTMLImageElement"},
	{"HTMLInputElement"},
	{"HTMLLIElement"},
	{"HTMLLabelElement"},
	{"HTMLLegendElement"},
	{"HTMLLinkElement"},
	{"HTMLMapElement"},
	{"HTMLMarqueeElement"},
	{"HTMLMediaElement"},
	{"HTMLMenuElement"},
	{"HTMLMetaElement"},
	{"HTMLMeterElement"},
	{"HTMLModElement"},
	{"HTMLOListElement"},
	{"HTMLObjectElement"},
	{"HTMLOptGroupElement"},
	{"HTMLOptionElement"},
	{"HTMLOptionsCollection"},
	{"HTMLOutputElement"},
	{"HTMLParagraphElement"},
	{"HTMLParamElement"},
	{"HTMLPictureElement"},
	{"HTMLPreElement"},
	{"HTMLProgressElement"},
	{"HTMLQuoteElement"},
	{"HTMLScriptElement"},
	{"HTMLSelectElement"},
	{"HTMLSlotElement"},
	{"HTMLSourceElement"},
	{"HTMLSpanElement"},
	{"HTMLStyleElement"},
	{"HTMLTableCaptionElement"},
	{"HTMLTableCellElement"},
	{"HTMLTableColElement"},
	{"HTMLTableElement"},
	{"HTMLTableRowElement"},
	{"HTMLTableSectionElement"},
	{"HTMLTemplateElement"},
	{"HTMLTextAreaElement"},
	{"HTMLTimeElement"},
	{"HTMLTitleElement"},
	{"HTMLTrackElement"},
	{"HTMLUListElement"},
	{"HTMLUnknownElement"},
	{"HTMLVideoElement"},
	{"HashChangeEvent"},
	{"Headers"},
	{"History"},
	{"IDBCursor"},
	{"IDBCursorWithValue"},
	{"IDBDatabase"},
	{"IDBFactory"},
	{"IDBIndex"},
	{"IDBKeyRange"},
	{"IDBObjectStore"},
	{"IDBOpenDBRequest"},
	{"IDBRequest"},
	{"IDBTransaction"},
	{"IDBVersionChangeEvent"},
	{"Image"},
	{"ImageData"},
	{"InputEvent"},
	{"IntersectionObserver"},
	{"IntersectionObserverEntry"},
	{"KeyboardEvent"},
	{"KeyframeEffect"},
	{"Location"},
	{"MediaCapabilities"},
	{"MediaElementAudioSourceNode"},
	{"MediaEncryptedEvent"},
	{"MediaError"},
	{"MediaList"},
	{"MediaQueryList"},
	{"MediaQueryListEvent"},
	{"MediaRecorder"},
	{"MediaSource"},
	{"MediaStream"},
	{"MediaStreamAudioDestinationNode"},
	{"MediaStreamAudioSourceNode"},
	{"MediaStreamTrack"},
	{"MediaStreamTrackEvent"},
	{"MimeType"},
	{"MimeTypeArray"},
	{"MouseEvent"},
	{"MutationEvent"},
	{"MutationObserver"},
	{"MutationRecord"},
	{"NamedNodeMap"},
	{"Navigator"},
	{"Node"},
	{"NodeFilter"},
	{"NodeIterator"},
	{"NodeList"},
	{"Notification"},
	{"OfflineAudioCompletionEvent"},
	{"Option"},
	{"OscillatorNode"},
	{"PageTransitionEvent"},
	{"Path2D"},
	{"Performance"},
	{"PerformanceEntry"},
	{"PerformanceMark"},
	{"PerformanceMeasure"},
	{"PerformanceNavigation"},
	{"PerformanceObserver"},
	{"PerformanceObserverEntryList"},
	{"PerformanceResourceTiming"},
	{"PerformanceTiming"},
	{"PeriodicWave"},
	{"Plugin"},
	{"PluginArray"},
	{"PointerEvent"},
	{"PopStateEvent"},
	{"ProcessingInstruction"},
	{"ProgressEvent"},
	{"PromiseRejectionEvent"},
	{"RTCCertificate"},
	{"RTCDTMFSender"},
	{"RTCDTMFToneChangeEvent"},
	{"RTCDataChannel"},
	{"RTCDataChannelEvent"},
	{"RTCIceCandidate"},
	{"RTCPeerConnection"},
	{"RTCPeerConnectionIceEvent"},
	{"RTCRtpReceiver"},
	{"RTCRtpSender"},
	{"RTCRtpTransceiver"},
	{"RTCSessionDescription"},
	{"RTCStatsReport"},
	{"RTCTrackEvent"},
	{"RadioNodeList"},
	{"Range"},
	{"ReadableStream"},
	{"Request"},
	{"ResizeObserver"},
	{"ResizeObserverEntry"},
	{"Response"},
	{"Screen"},
	{"ScriptProcessorNode"},
	{"SecurityPolicyViolationEvent"},
	{"Selection"},
	{"ShadowRoot"},
	{"SourceBuffer"},
	{"SourceBufferList"},
	{"SpeechSynthesisEvent"},
	{"SpeechSynthesisUtterance"},
	{"StaticRange"},
	{"Storage"},
	{"StorageEvent"},
	{"StyleSheet"},
	{"StyleSheetList"},
	{"Text"},
	{"TextMetrics"},
	{"TextTrack"},
	{"TextTrackCue"},
	{"TextTrackCueList"},
	{"TextTrackList"},
	{"TimeRanges"},
	{"TrackEvent"},
	{"TransitionEvent"},
	{"TreeWalker"},
	{"UIEvent"},
	{"VTTCue"},
	{"ValidityState"},
	{"VisualViewport"},
	{"WaveShaperNode"},
	{"WebGLActiveInfo"},
	{"WebGLBuffer"},
	{"WebGLContextEvent"},
	{"WebGLFramebuffer"},
	{"WebGLProgram"},
	{"WebGLQuery"},
	{"WebGLRenderbuffer"},
	{"WebGLRenderingContext"},
	{"WebGLSampler"},
	{"WebGLShader"},
	{"WebGLShaderPrecisionFormat"},
	{"WebGLSync"},
	{"WebGLTexture"},
	{"WebGLUniformLocation"},
	{"WebKitCSSMatrix"},
	{"WebSocket"},
	{"WheelEvent"},
	{"Window"},
	{"Worker"},
	{"XMLDocument"},
	{"XMLHttpRequest"},
	{"XMLHttpRequestEventTarget"},
	{"XMLHttpRequestUpload"},
	{"XMLSerializer"},
	{"XPathEvaluator"},
	{"XPathExpression"},
	{"XPathResult"},
	{"XSLTProcessor"},
	{"alert"},
	{"atob"},
	{"blur"},
	{"btoa"},
	{"cancelAnimationFrame"},
	{"captureEvents"},
	{"close"},
	{"closed"},
	{"confirm"},
	{"customElements"},
	{"devicePixelRatio"},
	{"document"},
	{"event"},
	{"fetch"},
	{"find"},
	{"focus"},
	{"frameElement"},
	{"frames"},
	{"getComputedStyle"},
	{"getSelection"},
	{"history"},
	{"indexedDB"},
	{"isSecureContext"},
	{"length"},
	{"location"},
	{"locationbar"},
	{"matchMedia"},
	{"menubar"},
	{"moveBy"},
	{"moveTo"},
	{"name"},
	{"navigator"},
	{"onabort"},
	{"onafterprint"},
	{"onanimationend"},
	{"onanimationiteration"},
	{"onanimationstart"},
	{"onbeforeprint"},
	{"onbeforeunload"},
	{"onblur"},
	{"oncanplay"},
	{"oncanplaythrough"},
	{"onchange"},
	{"onclick"},
	{"oncontextmenu"},
	{"oncuechange"},
	{"ondblclick"},
	{"ondrag"},
	{"ondragend"},
	{"ondragenter"},
	{"ondragleave"},
	{"ondragover"},
	{"ondragstart"},
	{"ondrop"},
	{"ondurationchange"},
	{"onemptied"},
	{"onended"},
	{"onerror"},
	{"onfocus"},
	{"ongotpointercapture"},
	{"onhashchange"},
	{"oninput"},
	{"oninvalid"},
	{"onkeydown"},
	{"onkeypress"},
	{"onkeyup"},
	{"onlanguagechange"},
	{"onload"},
	{"onloadeddata"},
	{"onloadedmetadata"},
	{"onloadstart"},
	{"onlostpointercapture"},
	{"onmessage"},
	{"onmousedown"},
	{"onmouseenter"},
	{"onmouseleave"},
	{"onmousemove"},
	{"onmouseout"},
	{"onmouseover"},
	{"onmouseup"},
	{"onoffline"},
	{"ononline"},
	{"onpagehide"},
	{"onpageshow"},
	{"onpause"},
	{"onplay"},
	{"onplaying"},
	{"onpointercancel"},
	{"onpointerdown"},
	{"onpointerenter"},
	{"onpointerleave"},
	{"onpointermove"},
	{"onpointerout"},
	{"onpointerover"},
	{"onpointerup"},
	{"onpopstate"},
	{"onprogress"},
	{"onratechange"},
	{"onrejectionhandled"},
	{"onreset"},
	{"onresize"},
	{"onscroll"},
	{"onseeked"},
	{"onseeking"},
	{"onselect"},
	{"onstalled"},
	{"onstorage"},
	{"onsubmit"},
	{"onsuspend"},
	{"ontimeupdate"},
	{"ontoggle"},
	{"ontransitioncancel"},
	{"ontransitionend"},
	{"ontransitionrun"},
	{"ontransitionstart"},
	{"onunhandledrejection"},
	{"onunload"},
	{"onvolumechange"},
	{"onwaiting"},
	{"onwebkitanimationend"},
	{"onwebkitanimationiteration"},
	{"onwebkitanimationstart"},
	{"onwebkittransitionend"},
	{"onwheel"},
	{"open"},
	{"opener"},
	{"origin"},
	{"outerHeight"},
	{"outerWidth"},
	{"parent"},
	{"performance"},
	{"personalbar"},
	{"postMessage"},
	{"print"},
	{"prompt"},
	{"releaseEvents"},
	{"requestAnimationFrame"},
	{"resizeBy"},
	{"resizeTo"},
	{"screen"},
	{"screenLeft"},
	{"screenTop"},
	{"screenX"},
	{"screenY"},
	{"scroll"},
	{"scrollBy"},
	{"scrollTo"},
	{"scrollbars"},
	{"self"},
	{"speechSynthesis"},
	{"status"},
	{"statusbar"},
	{"stop"},
	{"toolbar"},
	{"top"},
	{"webkitURL"},
	{"window"},
}

type DefineArgs struct {
	Loc             logger.Loc
	FindSymbol      func(logger.Loc, string) js_ast.Ref
	SymbolForDefine func(int) js_ast.Ref
}

type DefineFunc func(DefineArgs) js_ast.E

type DefineData struct {
	DefineFunc DefineFunc

True if accessing this value is known to not have any side effects. For example, a bare reference to "Object.create" can be removed because it does not have any observable side effects.

	CanBeRemovedIfUnused bool

True if a call to this value is known to not have any side effects. For example, a bare call to "Object()" can be removed because it does not have any observable side effects.

	CallCanBeUnwrappedIfUnused bool

Set to true to warn users that this should be defined if it's not already.

	WarnAboutLackOfDefine bool
}

func mergeDefineData(old DefineData, new DefineData) DefineData {
	if old.CanBeRemovedIfUnused {
		new.CanBeRemovedIfUnused = true
	}
	if old.CallCanBeUnwrappedIfUnused {
		new.CallCanBeUnwrappedIfUnused = true
	}

Don't warn if the user defined this

	new.WarnAboutLackOfDefine = false
	return new
}

type DotDefine struct {
	Parts []string
	Data  DefineData
}

type ProcessedDefines struct {
	IdentifierDefines map[string]DefineData
	DotDefines        map[string][]DotDefine
}

This transformation is expensive, so we only want to do it once. Make sure to only call processDefines() once per compilation. Unfortunately Golang doesn't have an efficient way to copy a map and the overhead of copying all of the properties into a new map once for every new parser noticeably slows down our benchmarks.

Optimization: reuse known globals if there are no user-specified defines

	hasUserDefines := len(userDefines) != 0
	if !hasUserDefines {
		processedGlobalsMutex.Lock()
		if processedGlobals != nil {
			defer processedGlobalsMutex.Unlock()
			return *processedGlobals
		}
		processedGlobalsMutex.Unlock()
	}

	result := ProcessedDefines{
		IdentifierDefines: make(map[string]DefineData),
		DotDefines:        make(map[string][]DotDefine),
	}

Mark these property accesses as free of side effects. That means they can be removed if their result is unused. We can't just remove all unused property accesses since property accesses can have side effects. For example, the property access "a.b.c" has the side effect of throwing an exception if "a.b" is undefined.

	for _, parts := range knownGlobals {
		tail := parts[len(parts)-1]
		if len(parts) == 1 {
			result.IdentifierDefines[tail] = DefineData{CanBeRemovedIfUnused: true}
		} else {
			result.DotDefines[tail] = append(result.DotDefines[tail], DotDefine{Parts: parts, Data: DefineData{CanBeRemovedIfUnused: true}})
		}
	}

Swap in certain literal values because those can be constant folded

	result.IdentifierDefines["undefined"] = DefineData{
		DefineFunc: func(DefineArgs) js_ast.E { return &js_ast.EUndefined{} },
	}
	result.IdentifierDefines["NaN"] = DefineData{
		DefineFunc: func(DefineArgs) js_ast.E { return &js_ast.ENumber{Value: math.NaN()} },
	}
	result.IdentifierDefines["Infinity"] = DefineData{
		DefineFunc: func(DefineArgs) js_ast.E { return &js_ast.ENumber{Value: math.Inf(1)} },
	}

Warn about use of this without a define

	result.DotDefines["NODE_ENV"] = []DotDefine{{
		Parts: []string{"process", "env", "NODE_ENV"},
		Data:  DefineData{WarnAboutLackOfDefine: true},
	}}

Then copy the user-specified defines in afterwards, which will overwrite any known globals above.

	for key, data := range userDefines {
		parts := strings.Split(key, ".")

Identifier defines are special-cased

		if len(parts) == 1 {
			result.IdentifierDefines[key] = mergeDefineData(result.IdentifierDefines[key], data)
			continue
		}

		tail := parts[len(parts)-1]
		dotDefines := result.DotDefines[tail]
		found := false

Try to merge with existing dot defines first

		for i, define := range dotDefines {
			if arePartsEqual(parts, define.Parts) {
				define := &dotDefines[i]
				define.Data = mergeDefineData(define.Data, data)
				found = true
				break
			}
		}

		if !found {
			dotDefines = append(dotDefines, DotDefine{Parts: parts, Data: data})
		}
		result.DotDefines[tail] = dotDefines
	}

Potentially cache the result for next time

	if !hasUserDefines {
		processedGlobalsMutex.Lock()
		defer processedGlobalsMutex.Unlock()
		if processedGlobals == nil {
			processedGlobals = &result
		}
	}
	return result
}

func arePartsEqual(a []string, b []string) bool {
	if len(a) != len(b) {
		return false
	}
	for i := range a {
		if a[i] != b[i] {
			return false
		}
	}
	return true