diff --git a/packages/compiler/ambient/scriptc-overrides.d.ts b/packages/compiler/ambient/scriptc-overrides.d.ts index 2dafbcdf0..376eba9d5 100644 --- a/packages/compiler/ambient/scriptc-overrides.d.ts +++ b/packages/compiler/ambient/scriptc-overrides.d.ts @@ -70,3 +70,24 @@ interface PromiseConstructor { reject: (reason: Error) => void; }; } + +/* Carriers of the types the lowerer gives untyped JavaScript collections + * whose uses prove them (js-collection-types.ts). Nothing reads them at run + * time. */ +declare namespace __scriptcInferredCollections { + const map_string_string: Map; + const map_string_number: Map; + const map_string_boolean: Map; + const map_number_string: Map; + const map_number_number: Map; + const map_number_boolean: Map; + const map_boolean_string: Map; + const map_boolean_number: Map; + const map_boolean_boolean: Map; + const set_string: Set; + const set_number: Set; + const set_boolean: Set; + const array_string: string[]; + const array_number: number[]; + const array_boolean: boolean[]; +} diff --git a/packages/compiler/src/frontend/lowering/js-collection-types.ts b/packages/compiler/src/frontend/lowering/js-collection-types.ts new file mode 100644 index 000000000..2be3c067f --- /dev/null +++ b/packages/compiler/src/frontend/lowering/js-collection-types.ts @@ -0,0 +1,519 @@ +/* Types of untyped JavaScript collections that their uses prove. + * + * In a JavaScript file, `const m = new Map()`, `new Set()` and `[]` type as + * Map, Set and any[] to the checker, so every use lowers to + * the checked-dynamic collection operations. When every reference of such a + * `const` is a direct use of the collection, the value never leaves the + * binding. If its keys, values or elements are then each one primitive type + * wherever the program writes and looks them up, the binding lowers as the + * typed Map, Set or T[], as a JSDoc @type would make it: + * + * - Map: `m.get(k)`, `m.has(k)`, `m.delete(k)`, `m.clear()`, `m.size`, and + * `m.set(k, v)` as a statement (its result is the map). + * - Set: `s.add(k)` as a statement, `s.has(k)`, `s.delete(k)`, `s.clear()`, + * `s.size`. + * - Array: `a.push(...)`, `a.pop()`, `a.shift()`, `a.at(i)`, `a.includes(v)`, + * `a.indexOf(v)`, `a.join(separator)`, `a.length`. + * + * Any other reference (passing, returning, storing, exporting, iterating, + * spreading, inspecting the collection, an optional call), a direct `eval` + * in the file, or any doubt about a type keeps the binding untyped. + * + * The types come from carrier declarations in scriptc-overrides.d.ts, which + * only the lowering program includes. */ + +import * as ts from "../ts7/adapter.js"; +import { isJsSourceFile } from "../program.js"; +import { overridesDtsPath } from "../dts-paths.js"; +import type { Lowerer } from "./lowerer.js"; + +type Primitive = "string" | "number" | "boolean"; +const PRIMITIVES: readonly Primitive[] = ["string", "number", "boolean"]; + +type Collection = "map" | "set" | "array"; + +interface Candidate { + readonly kind: Collection; + readonly declaration: ts.VariableDeclaration; + /** Every identifier that names the binding, its declaration's included. */ + readonly names: ts.Identifier[]; + /** Map keys or Set members written by set/add. */ + readonly keyWrites: ts.Expression[]; + /** Map values written by set. Array elements written by push. */ + readonly valueWrites: ts.Expression[]; + /** Arguments compared with keys or elements: get/has/delete, includes/indexOf. */ + readonly lookups: ts.Expression[]; + /** Array indexes passed to at(). */ + readonly indexes: ts.Expression[]; + /** Separators passed to join(). */ + readonly separators: ts.Expression[]; + key: Primitive | undefined; + value: Primitive | undefined; +} + +const MAP_LOOKUPS = new Set(["get", "has", "delete"]); +const SET_LOOKUPS = new Set(["has", "delete"]); +const ARRAY_READS = new Set(["pop", "shift"]); +const ARRAY_SEARCHES = new Set(["includes", "indexOf"]); + +/** The inferred type of the binding a `new Map()` or `new Set()` initializes, + * which the construction adopts. */ +export function initializedCollectionType( + lowerer: Lowerer, + expr: ts.NewExpression, +): ts.Type | null { + const declaration = expr.parent; + return declaration !== undefined && + ts.isVariableDeclaration(declaration) && + declaration.initializer === expr && + ts.isIdentifier(declaration.name) + ? inferredCollectionType(lowerer, declaration.name) + : null; +} + +/** The inferred collection type of an identifier that names a proven + * binding, or null. Computed for every JavaScript file of the program on + * first use. */ +export function inferredCollectionType(lowerer: Lowerer, node: ts.Identifier): ts.Type | null { + const types = (lowerer.inferredCollectionTypes ??= inferProgram(lowerer)); + return types.size === 0 ? null : (types.get(node) ?? null); +} + +function inferProgram(lowerer: Lowerer): Map { + const out = new Map(); + const carriers = carrierTypes(lowerer); + if (carriers === null) return out; + for (const file of lowerer.program.getSourceFiles()) { + if (file.isDeclarationFile || !isJsSourceFile(file)) continue; + for (const candidate of inferFile(lowerer, file)) { + const name = + candidate.kind === "map" + ? `map_${candidate.key}_${candidate.value}` + : candidate.kind === "set" + ? `set_${candidate.key}` + : `array_${candidate.value}`; + const type = carriers.get(name); + if (type === undefined) continue; + for (const id of candidate.names) out.set(id, type); + } + } + return out; +} + +/** The carrier declarations' types, by name (`map_string_number`, + * `set_number`, `array_string`, ...), or null when the lowering program does + * not include them. */ +function carrierTypes(lowerer: Lowerer): Map | null { + const file = lowerer.program.getSourceFile(overridesDtsPath()); + if (file === undefined) return null; + const out = new Map(); + for (const statement of file.statements.nodes) { + if ( + !ts.isModuleDeclaration(statement) || + !ts.isIdentifier(statement.name) || + statement.name.text !== "__scriptcInferredCollections" || + statement.body === undefined || + !ts.isModuleBlock(statement.body) + ) + continue; + for (const member of statement.body.statements.nodes) { + if (!ts.isVariableStatement(member)) continue; + for (const declaration of member.declarationList.declarations.nodes) + if (ts.isIdentifier(declaration.name)) + out.set(declaration.name.text, lowerer.checker.getTypeAtLocation(declaration.name)); + } + } + return out.size > 0 ? out : null; +} + +function inferFile(lowerer: Lowerer, file: ts.SourceFile): Candidate[] { + const candidates = new Map(); + let directEval = false; + const declarations = (node: ts.Node): void => { + if ( + ts.isCallExpression(node) && + ts.isIdentifier(node.expression) && + node.expression.text === "eval" + ) + directEval = true; + if (ts.isVariableDeclaration(node)) { + const kind = candidateKind(lowerer, node); + const symbol = kind !== null ? lowerer.checker.getSymbolAtLocation(node.name) : undefined; + if (kind !== null && symbol !== undefined) + candidates.set(symbol, { + kind, + declaration: node, + names: [node.name as ts.Identifier], + keyWrites: [], + valueWrites: [], + lookups: [], + indexes: [], + separators: [], + key: undefined, + value: undefined, + }); + } + ts.forEachChild(node, declarations); + }; + declarations(file); + if (directEval || candidates.size === 0) return []; + + const names = new Set( + [...candidates.values()].map((c) => (c.declaration.name as ts.Identifier).text), + ); + const refused = new Set(); + const references = (node: ts.Node): void => { + if (ts.isIdentifier(node) && names.has(node.text)) { + const symbol = referencedSymbol(lowerer, node); + const candidate = symbol !== undefined ? candidates.get(symbol) : undefined; + if (symbol !== undefined && candidate !== undefined && node !== candidate.declaration.name) { + if (recordUse(candidate, node)) candidate.names.push(node); + else refused.add(symbol); + } + } + ts.forEachChild(node, references); + }; + references(file); + for (const symbol of refused) candidates.delete(symbol); + const proven = [...candidates.values()].filter( + (c) => c.valueWrites.length > 0 || c.keyWrites.length > 0, + ); + solve(lowerer, proven); + return proven.filter((c) => + c.kind === "map" ? c.key && c.value : c.kind === "set" ? c.key : c.value, + ); +} + +/** The collection a `const` declaration starts empty, when the checker + * types it as an untyped Map, Set or array. */ +function candidateKind(lowerer: Lowerer, declaration: ts.VariableDeclaration): Collection | null { + if (!ts.isIdentifier(declaration.name) || declaration.initializer === undefined) return null; + const list = declaration.parent; + if (!ts.isVariableDeclarationList(list) || (list.flags & ts.NodeFlags.Const) === 0) return null; + const statement = list.parent; + if ( + ts.isVariableStatement(statement) && + ts.getModifiers(statement)?.some((m) => m.kind === ts.SyntaxKind.ExportKeyword) + ) + return null; + const init = declaration.initializer; + let kind: Collection | null = null; + if (ts.isArrayLiteralExpression(init) && init.elements.nodes.length === 0) kind = "array"; + else if ( + ts.isNewExpression(init) && + init.typeArguments === undefined && + (init.arguments?.nodes.length ?? 0) === 0 + ) { + if (lowerer.isStdlibGlobal(init.expression, "Map")) kind = "map"; + else if (lowerer.isStdlibGlobal(init.expression, "Set")) kind = "set"; + } + if (kind === null) return null; + // A JSDoc type, or anything else the checker already knows, stands. + const type = lowerer.checker.getTypeAtLocation(declaration.name); + const args = + kind === "array" + ? lowerer.checker.isArrayType(type) + ? lowerer.checker.getTypeArguments(type as ts.TypeReference) + : [] + : lowerer.checker.getTypeArguments(type as ts.TypeReference); + const arity = kind === "map" ? 2 : 1; + if (args.length !== arity || !args.every((a) => (a.flags & ts.TypeFlags.Any) !== 0)) return null; + return kind; +} + +function referencedSymbol(lowerer: Lowerer, id: ts.Identifier): ts.Symbol | undefined { + const parent = id.parent; + if (parent !== undefined && ts.isShorthandPropertyAssignment(parent) && parent.name === id) + return lowerer.checker.getShorthandAssignmentValueSymbol(parent); + return lowerer.checker.getSymbolAtLocation(id); +} + +/** Records a reference's use, or answers false when the reference is not + * one of the collection uses this inference proves. */ +function recordUse(candidate: Candidate, id: ts.Identifier): boolean { + const access = id.parent; + if ( + access === undefined || + !ts.isPropertyAccessExpression(access) || + access.expression !== id || + access.questionDotToken !== undefined + ) + return false; + const name = access.name.text; + const call = access.parent; + if (call !== undefined && ts.isCallExpression(call) && call.expression === access) { + if (call.questionDotToken !== undefined) return false; + const args = call.arguments.nodes; + if (args.some(ts.isSpreadElement)) return false; + switch (candidate.kind) { + case "map": + if (MAP_LOOKUPS.has(name) && args.length === 1) + return (candidate.lookups.push(args[0]!), true); + if (name === "clear") return args.length === 0; + if (name === "set" && args.length === 2 && isStatement(call)) { + candidate.keyWrites.push(args[0]!); + candidate.valueWrites.push(args[1]!); + return true; + } + return false; + case "set": + if (SET_LOOKUPS.has(name) && args.length === 1) + return (candidate.lookups.push(args[0]!), true); + if (name === "clear") return args.length === 0; + if (name === "add" && args.length === 1 && isStatement(call)) + return (candidate.keyWrites.push(args[0]!), true); + return false; + case "array": + if (name === "push") return (candidate.valueWrites.push(...args), true); + if (ARRAY_READS.has(name)) return args.length === 0; + if (name === "at" && args.length === 1) return (candidate.indexes.push(args[0]!), true); + if (ARRAY_SEARCHES.has(name) && args.length === 1) + return (candidate.lookups.push(args[0]!), true); + if (name === "join" && args.length <= 1) return (candidate.separators.push(...args), true); + return false; + } + } + return (candidate.kind === "array" ? name === "length" : name === "size") && isPlainRead(access); +} + +function isStatement(call: ts.CallExpression): boolean { + let node: ts.Node = call; + while (node.parent !== undefined && ts.isParenthesizedExpression(node.parent)) node = node.parent; + return node.parent !== undefined && ts.isExpressionStatement(node.parent); +} + +/** A read that neither writes nor deletes the property. */ +function isPlainRead(access: ts.PropertyAccessExpression): boolean { + let node: ts.Node = access; + while (node.parent !== undefined && ts.isParenthesizedExpression(node.parent)) node = node.parent; + const parent = node.parent; + if (parent === undefined) return false; + if ( + ts.isBinaryExpression(parent) && + parent.left === node && + isAssignment(parent.operatorToken.kind) + ) + return false; + if ( + (ts.isPrefixUnaryExpression(parent) || ts.isPostfixUnaryExpression(parent)) && + (parent.operator === ts.SyntaxKind.PlusPlusToken || + parent.operator === ts.SyntaxKind.MinusMinusToken) + ) + return false; + return !ts.isDeleteExpression(parent); +} + +function isAssignment(kind: ts.SyntaxKind): boolean { + return kind >= ts.SyntaxKind.FirstAssignment && kind <= ts.SyntaxKind.LastAssignment; +} + +/** Decides each candidate's key and value types: a fixed point in which a + * decided candidate's reads type the expressions built from them. */ +function solve(lowerer: Lowerer, candidates: Candidate[]): void { + const bySymbol = new Map(); + for (const c of candidates) { + const symbol = lowerer.checker.getSymbolAtLocation(c.declaration.name); + if (symbol) bySymbol.set(symbol, c); + } + for (let changed = true; changed;) { + changed = false; + for (const c of candidates) { + if (c.kind !== "array" && c.key === undefined) { + const key = uniform(lowerer, bySymbol, c.keyWrites); + if (key !== null) { + c.key = key; + changed = true; + } + } + if (c.kind !== "set" && c.value === undefined) { + // Each candidate type is assumed for this collection's own reads. + const accepted = PRIMITIVES.filter((assumed) => { + c.value = assumed; + const found = uniform(lowerer, bySymbol, c.valueWrites); + c.value = undefined; + return found === assumed; + }); + if (accepted.length === 1) { + c.value = accepted[0]; + changed = true; + } + } + } + } + for (const c of candidates) { + const element = c.kind === "array" ? c.value : c.key; + // Lookups compare with the stored type; an index is a number. + const lookupsAgree = + element !== undefined && + c.lookups.every((e) => primitiveOf(lowerer, bySymbol, e, new Set()) === element) && + c.indexes.every((e) => primitiveOf(lowerer, bySymbol, e, new Set()) === "number") && + c.separators.every((e) => primitiveOf(lowerer, bySymbol, e, new Set()) === "string"); + if (!lookupsAgree) { + c.key = undefined; + c.value = undefined; + } + } +} + +/** The one primitive type of every expression, or null. */ +function uniform( + lowerer: Lowerer, + bySymbol: Map, + exprs: readonly ts.Expression[], +): Primitive | null { + let found: Primitive | null = null; + for (const e of exprs) { + const p = primitiveOf(lowerer, bySymbol, e, new Set()); + if (p === null || (found !== null && p !== found)) return null; + found = p; + } + return found; +} + +function checkerPrimitive(type: ts.Type): Primitive | null { + const flags = type.flags; + if (flags & (ts.TypeFlags.String | ts.TypeFlags.StringLiteral)) return "string"; + if (flags & (ts.TypeFlags.Number | ts.TypeFlags.NumberLiteral)) return "number"; + if (flags & (ts.TypeFlags.Boolean | ts.TypeFlags.BooleanLiteral)) return "boolean"; + return null; +} + +/** The primitive type `e` always evaluates to, or null. The checker answers + * where it knows; where it types `e` as `any`, the value's structure does: + * a read of a decided candidate, arithmetic and comparisons over such + * values, and constants defined from them. */ +function primitiveOf( + lowerer: Lowerer, + bySymbol: Map, + e: ts.Expression, + visiting: Set, +): Primitive | null { + const type = lowerer.checker.getTypeAtLocation(e); + if ((type.flags & (ts.TypeFlags.Any | ts.TypeFlags.Unknown)) === 0) return checkerPrimitive(type); + const of = (x: ts.Expression): Primitive | null => primitiveOf(lowerer, bySymbol, x, visiting); + if (ts.isParenthesizedExpression(e)) return of(e.expression); + if (ts.isPrefixUnaryExpression(e)) { + if (e.operator === ts.SyntaxKind.ExclamationToken) return "boolean"; + return e.operator !== ts.SyntaxKind.PlusPlusToken && + e.operator !== ts.SyntaxKind.MinusMinusToken && + of(e.operand) === "number" + ? "number" + : null; + } + if (ts.isConditionalExpression(e)) { + const yes = of(e.whenTrue); + return yes !== null && yes === of(e.whenFalse) ? yes : null; + } + if (ts.isBinaryExpression(e)) { + const op = e.operatorToken.kind; + switch (op) { + case ts.SyntaxKind.LessThanToken: + case ts.SyntaxKind.GreaterThanToken: + case ts.SyntaxKind.LessThanEqualsToken: + case ts.SyntaxKind.GreaterThanEqualsToken: + case ts.SyntaxKind.EqualsEqualsEqualsToken: + case ts.SyntaxKind.ExclamationEqualsEqualsToken: + case ts.SyntaxKind.EqualsEqualsToken: + case ts.SyntaxKind.ExclamationEqualsToken: + return "boolean"; + case ts.SyntaxKind.QuestionQuestionToken: + case ts.SyntaxKind.BarBarToken: { + // `m.get(k) ?? d` and `a.pop() || d`: the stored type or a default of it. + const stored = storedRead(lowerer, bySymbol, e.left); + const fallback = of(e.right); + return stored !== null && stored === fallback ? stored : null; + } + case ts.SyntaxKind.PlusToken: { + const left = of(e.left); + const right = of(e.right); + if (left === "number" && right === "number") return "number"; + return left !== null && right !== null && (left === "string" || right === "string") + ? "string" + : null; + } + case ts.SyntaxKind.MinusToken: + case ts.SyntaxKind.AsteriskToken: + case ts.SyntaxKind.SlashToken: + case ts.SyntaxKind.PercentToken: + case ts.SyntaxKind.AsteriskAsteriskToken: + case ts.SyntaxKind.BarToken: + case ts.SyntaxKind.AmpersandToken: + case ts.SyntaxKind.CaretToken: + case ts.SyntaxKind.LessThanLessThanToken: + case ts.SyntaxKind.GreaterThanGreaterThanToken: + case ts.SyntaxKind.GreaterThanGreaterThanGreaterThanToken: + return of(e.left) === "number" && of(e.right) === "number" ? "number" : null; + default: + return null; + } + } + if (ts.isCallExpression(e) || ts.isPropertyAccessExpression(e)) + return candidateRead(lowerer, bySymbol, e); + // A constant defined from such an expression. + if (ts.isIdentifier(e) && !visiting.has(e)) { + const symbol = lowerer.checker.getSymbolAtLocation(e); + const declaration = symbol?.valueDeclaration; + if ( + declaration !== undefined && + ts.isVariableDeclaration(declaration) && + declaration.initializer !== undefined && + ts.isVariableDeclarationList(declaration.parent) && + (declaration.parent.flags & ts.NodeFlags.Const) !== 0 + ) { + visiting.add(e); + const p = primitiveOf(lowerer, bySymbol, declaration.initializer, visiting); + visiting.delete(e); + return p; + } + } + return null; +} + +/** The candidate a use reads, when `e` is `c.member` or `c.member(...)` of a + * candidate `c`. */ +function candidateOf( + lowerer: Lowerer, + bySymbol: Map, + e: ts.Expression, +): { candidate: Candidate; member: string } | null { + const access = ts.isCallExpression(e) ? e.expression : e; + if (!ts.isPropertyAccessExpression(access) || !ts.isIdentifier(access.expression)) return null; + const symbol = lowerer.checker.getSymbolAtLocation(access.expression); + const candidate = symbol !== undefined ? bySymbol.get(symbol) : undefined; + return candidate !== undefined ? { candidate, member: access.name.text } : null; +} + +/** The type of a candidate's read that may answer undefined: `m.get(k)`, + * `a.pop()`, `a.shift()`, `a.at(i)`. */ +function storedRead( + lowerer: Lowerer, + bySymbol: Map, + e: ts.Expression, +): Primitive | null { + while (ts.isParenthesizedExpression(e)) e = e.expression; + if (!ts.isCallExpression(e)) return null; + const read = candidateOf(lowerer, bySymbol, e); + if (read === null) return null; + const { candidate, member } = read; + if (candidate.kind === "map" && member === "get") return candidate.value ?? null; + if (candidate.kind === "array" && (ARRAY_READS.has(member) || member === "at")) + return candidate.value ?? null; + return null; +} + +/** The type of a candidate's read that always answers a value: size, + * length, has, includes, indexOf, push. */ +function candidateRead( + lowerer: Lowerer, + bySymbol: Map, + e: ts.Expression, +): Primitive | null { + const read = candidateOf(lowerer, bySymbol, e); + if (read === null) return null; + const { candidate, member } = read; + if (!ts.isCallExpression(e)) return member === "size" || member === "length" ? "number" : null; + if (member === "has" || member === "includes" || member === "delete") return "boolean"; + if (member === "indexOf" || (candidate.kind === "array" && member === "push")) return "number"; + if (candidate.kind === "array" && member === "join") return "string"; + return null; +} diff --git a/packages/compiler/src/frontend/lowering/lower-classes.ts b/packages/compiler/src/frontend/lowering/lower-classes.ts index b829b6ddc..c4dd6bce1 100644 --- a/packages/compiler/src/frontend/lowering/lower-classes.ts +++ b/packages/compiler/src/frontend/lowering/lower-classes.ts @@ -113,6 +113,7 @@ import { PoisonError, dynFallbackType, jsFuncNameOf, newFnCtx, own } from "./low import { isAssertClassNew } from "./assert-instances.js"; import { isCjsRequireGlobal } from "./lower-node-module.js"; import { lowerArrayConstructor } from "./containers/array-construction.js"; +import { initializedCollectionType } from "./js-collection-types.js"; import { lowerMapSeedNew, lowerSetSeedNew } from "./containers/collection-methods.js"; import { lowerObjectConstructor } from "./containers/indexed-objects.js"; import { knownBufEncoding, lowerBufferConstruct } from "./containers/bytes.js"; @@ -10568,7 +10569,11 @@ export function lowerNew(lowerer: Lowerer, expr: ts.NewExpression): IrExpr { // expression). The CONTEXTUAL type carries the annotation — adopt // it when it is a supported map. TS type arguments keep winning: // their expression type already maps. - if (mapped?.kind !== "map" || contextualSeed) { + const inferred = initializedCollectionType(lowerer, expr); + if (inferred) { + tsType = inferred; + mapped = lowerer.mapTypeOf(inferred); + } else if (mapped?.kind !== "map" || contextualSeed) { const ctx = lowerer.checker.getContextualType(expr); const ctxMapped = ctx ? lowerer.mapTypeOf(ctx) : null; if (ctx && ctxMapped?.kind === "map") { @@ -10708,7 +10713,8 @@ export function lowerNew(lowerer: Lowerer, expr: ts.NewExpression): IrExpr { // `new Set()`: construct + bulk add from supported values, // including live collection cursors. Duplicates collapse in insertion order. if (ts.isIdentifier(identifier) && lowerer.isStdlibGlobal(identifier, "Set")) { - const tsType = lowerer.typeOf(expr); + const inferred = initializedCollectionType(lowerer, expr); + const tsType = inferred ?? lowerer.typeOf(expr); let mapped = lowerer.mapTypeOf(tsType); const fieldType = assignedThisFieldType(lowerer, expr); if (mapped?.kind !== "set" && fieldType?.kind === "set") mapped = fieldType; diff --git a/packages/compiler/src/frontend/lowering/lowerer.ts b/packages/compiler/src/frontend/lowering/lowerer.ts index af89c61a4..78d1fafad 100644 --- a/packages/compiler/src/frontend/lowering/lowerer.ts +++ b/packages/compiler/src/frontend/lowering/lowerer.ts @@ -156,6 +156,7 @@ import { trackClassFieldCreation, } from "./class-dynamic-dispatch.js"; import { guardClassAttributeWrites } from "./class-attributes.js"; +import { inferredCollectionType } from "./js-collection-types.js"; import { guardFrozenWrites, markSloppyRecordWrites } from "./frozen-records.js"; import { applyHandleProperties } from "./handle-properties.js"; import { installBufferValue } from "./containers/bytes.js"; @@ -2846,6 +2847,9 @@ export class Lowerer { /** Parameters read as `any` in the error-path copy of an error-first * callback. */ readonly anySymbols = new Set(); + /** The collection types that uses prove for untyped JavaScript bindings, + * by every identifier naming one (js-collection-types.ts). */ + inferredCollectionTypes: Map | undefined = undefined; /** overload-choice's answers per call, binding and function. */ readonly dynamicOverloadAnswers = new Map(); /** Error parameters of an error-first callback with a known value in @@ -9055,6 +9059,10 @@ export class Lowerer { } typeOf(node: ts.Node): ts.Type { + if (ts.isIdentifier(node)) { + const inferred = inferredCollectionType(this, node); + if (inferred) return inferred; + } if (this.anySymbols.size > 0 && this.readsAnySymbol(node)) return this.checker.getAnyType(); // A checked-dynamic argument that another overload could take at run // time leaves the resolved overload's return a guess, and JS bindings diff --git a/packages/compiler/test/js-collection-types.test.ts b/packages/compiler/test/js-collection-types.test.ts new file mode 100644 index 000000000..88e2006b7 --- /dev/null +++ b/packages/compiler/test/js-collection-types.test.ts @@ -0,0 +1,62 @@ +import { mkdtempSync, readFileSync, rmSync } from "node:fs"; +import { tmpdir } from "node:os"; +import { join } from "node:path"; +import { expect, test } from "vitest"; +import { compile, deserializeModule, validateModule } from "../src/index.js"; + +// Corpus 7985 exercises every refusal: only the collections whose uses +// prove their types lower as typed collections; the rest stay untyped. +test("untyped JavaScript collections take the types their uses prove, and only those", async () => { + const dir = mkdtempSync(join(tmpdir(), "scriptc-js-collection-types-")); + try { + const entry = join( + import.meta.dirname, + "../../../tests/corpus/7985-untyped-collection-types.mjs", + ); + const output = join(dir, "main.ir.json"); + const lowered = await compile(entry, { outputKind: "ir", outDir: dir, outPath: output }); + if (!lowered.ok) throw new Error(JSON.stringify(lowered.diagnostics)); + const module = deserializeModule(readFileSync(output, "utf8")); + expect(validateModule(module)).toEqual([]); + const types = new Map(module.globals.map((g) => [g.name, JSON.stringify(g.type)])); + const map = (key: string, value: string) => + JSON.stringify({ kind: "map", key: { kind: key }, value: { kind: value } }); + const set = (elem: string) => JSON.stringify({ kind: "set", elem: { kind: elem } }); + const array = (elem: string) => JSON.stringify({ kind: "array", elem: { kind: elem } }); + // Untyped collections hold checked-dynamic keys, values and elements. + const typed = (t: string) => !t.includes('"dyn"'); + expect(Object.fromEntries([...types].filter(([, t]) => typed(t)))).toEqual({ + counts: map("string", "f64"), + seen: set("f64"), + stack: array("f64"), + words: array("string"), + byNumber: map("f64", "string"), + nums: array("f64"), + flags: set("bool"), + cache: map("string", "f64"), + "%loaded": '{"kind":"bool"}', + }); + for (const untyped of [ + "strings", + "numbers", + "mixedKeys", + "mixedValues", + "mixedElements", + "passed", + "stored", + "iterated", + "eachSet", + "shown", + "chained", + "optional", + "indexed", + "truncated", + "spread", + "unread", + "exported", + ]) + expect(typed(types.get(untyped)!), untyped).toBe(false); + } finally { + rmSync(dir, { recursive: true, force: true }); + } +}); diff --git a/packages/compiler/test/ts7/baselines/order-parity/tests/corpus/7985-untyped-collection-types.mjs.json b/packages/compiler/test/ts7/baselines/order-parity/tests/corpus/7985-untyped-collection-types.mjs.json new file mode 100644 index 000000000..a807063cc --- /dev/null +++ b/packages/compiler/test/ts7/baselines/order-parity/tests/corpus/7985-untyped-collection-types.mjs.json @@ -0,0 +1,6 @@ +{ + "order": [ + "/tests/corpus/7985-untyped-collection-types.mjs" + ], + "diags": [] +} diff --git a/tests/corpus/7985-untyped-collection-types.mjs b/tests/corpus/7985-untyped-collection-types.mjs new file mode 100644 index 000000000..a60a2ea04 --- /dev/null +++ b/tests/corpus/7985-untyped-collection-types.mjs @@ -0,0 +1,116 @@ +// Untyped Maps, Sets and arrays whose uses prove their key, value and +// element types compile as typed collections; any other use keeps them +// untyped. Both must answer as Node does, including SameValueZero keys, +// lookups of another type, and every use that refuses the typing. + +// Typed: counters, membership sets and stacks used only through their +// methods. +const counts = new Map(); +const seen = new Set(); +const stack = []; +const words = []; +for (let i = 0; i < 40; i++) { + const key = "k" + (i % 7); + counts.set(key, (counts.get(key) ?? 0) + 1); + seen.add(i % 5); + stack.push(i * 2); + if (stack.length > 6) stack.shift(); + words.push(key); +} +console.log(counts.size, counts.get("k3"), counts.get("missing"), counts.has("k6"), counts.delete("k0"), counts.size); +console.log(seen.size, seen.has(4), seen.has(5), seen.delete(4), seen.has(4)); +console.log(stack.length, stack.at(-1), stack.at(0), stack.pop(), stack.includes(70), stack.indexOf(72), words.join("|").length); + +// SameValueZero keys and NaN elements on typed collections. +const byNumber = new Map(); +byNumber.set(NaN, "nan"); +byNumber.set(-0, "zero"); +byNumber.set(1.5, "x"); +console.log(byNumber.get(NaN), byNumber.get(0), byNumber.get(-0), byNumber.size, byNumber.has(1.5)); +const nums = []; +nums.push(NaN); +nums.push(-0); +console.log(nums.includes(NaN), nums.indexOf(NaN), nums.includes(0), nums.indexOf(0)); +const flags = new Set(); +flags.add(true); +console.log(flags.has(true), flags.has(false), flags.size); + +// Captured by a closure that only uses it. +const cache = new Map(); +const latest = () => cache.get("c") ?? -1; +console.log(latest()); +for (let i = 0; i < 3; i++) cache.set("c", i * 10); +console.log(latest(), cache.size); + +// Lookups of another type: the typing refuses, and the answers stay Node's. +const strings = new Map(); +strings.set("1", "one"); +console.log(strings.get(1), strings.get("1"), strings.has(1)); +const numbers = []; +numbers.push(1); +console.log(numbers.includes("1"), numbers.indexOf("1"), numbers.at("0")); + +// Mixed key, value and element types. +const mixedKeys = new Map(); +mixedKeys.set(1, "number"); +mixedKeys.set("1", "string"); +console.log(mixedKeys.size, mixedKeys.get(1), mixedKeys.get("1")); +const mixedValues = new Map(); +mixedValues.set("a", 1); +mixedValues.set("b", "two"); +console.log(mixedValues.get("a"), mixedValues.get("b")); +const mixedElements = []; +mixedElements.push(1); +mixedElements.push("two"); +console.log(mixedElements.join(","), mixedElements.length); + +// Escapes and other uses that keep the collection untyped. +const passed = new Map(); +passed.set("x", 1); +function sizeOf(m) { + return m.size; +} +console.log(sizeOf(passed)); +function make() { + const made = new Set(); + made.add("y"); + return made; +} +console.log(make().has("y")); +const stored = []; +stored.push(3); +const holder = { list: stored }; +holder.list.push(4); +console.log(stored.length, holder.list.join("+")); +const iterated = new Map(); +iterated.set("a", 1); +iterated.set("b", 2); +for (const [k, v] of iterated) console.log("entry", k, v); +const eachSet = new Set(); +eachSet.add(3); +eachSet.forEach((v) => console.log("member", v)); +const shown = new Map(); +shown.set("s", 1); +console.log(shown); +const chained = new Map(); +chained.set("a", 1).set("b", 2); +console.log(chained.size); +const optional = new Map(); +optional.set("o", 1); +console.log(optional?.get("o"), optional.get?.("o")); +const indexed = []; +indexed.push(1); +indexed[3] = 2; +console.log(indexed.length, indexed.join(",")); +const truncated = []; +truncated.push(1, 2, 3); +truncated.length = 1; +console.log(truncated.length, truncated.at(0)); +const spread = []; +spread.push(5); +console.log(Math.max(...spread)); +const unread = new Map(); +console.log(unread.size, unread.get("none")); +export const exported = new Map(); +exported.set("e", 1); +console.log(exported.get("e")); diff --git a/tests/harness/corpus-costs/7985-untyped-collection-types.mjs.json b/tests/harness/corpus-costs/7985-untyped-collection-types.mjs.json new file mode 100644 index 000000000..6915a85fe --- /dev/null +++ b/tests/harness/corpus-costs/7985-untyped-collection-types.mjs.json @@ -0,0 +1 @@ +{ "plain": 2400, "san": 2600 }