Improve coverage

src/ast/nodes/ForStatement.ts

@@ -42,7 +42,7 @@ export default class ForStatement extends StatementBase {
 		if (this.test) this.test.include(context, includeChildrenRecursively);
 		const { breakFlow } = context;
 		if (this.update) this.update.include(context, includeChildrenRecursively);
-		if (this.body) this.body.include(context, includeChildrenRecursively);
+		this.body.include(context, includeChildrenRecursively);
 		context.breakFlow = breakFlow;
 	}
 

src/ast/nodes/IfStatement.ts

@@ -19,16 +19,11 @@ export default class IfStatement extends StatementBase implements DeoptimizableE
 	test!: ExpressionNode;
 	type!: NodeType.tIfStatement;
 
-	private isTestValueAnalysed = false;
 	private testValue: LiteralValueOrUnknown;
 
 	bind() {
 		super.bind();
-		if (!this.isTestValueAnalysed) {
-			this.testValue = UnknownValue;
-			this.isTestValueAnalysed = true;
-			this.testValue = this.test.getLiteralValueAtPath(EMPTY_PATH, EMPTY_IMMUTABLE_TRACKER, this);
-		}
+		this.testValue = this.test.getLiteralValueAtPath(EMPTY_PATH, EMPTY_IMMUTABLE_TRACKER, this);
 	}
 
 	deoptimizeCache() {

src/ast/scopes/CatchScope.ts

@@ -8,7 +8,7 @@ export default class CatchScope extends ParameterScope {
 	addDeclaration(
 		identifier: Identifier,
 		context: AstContext,
-		init: ExpressionEntity | null = null,
+		init: ExpressionEntity | null,
 		isHoisted: boolean | 'function'
 	): LocalVariable {
 		if (isHoisted) {

src/ast/values.ts

@@ -47,6 +47,7 @@ export const UNKNOWN_EXPRESSION: ExpressionEntity = {
 	included: true,
 	toString: () => '[[UNKNOWN]]'
 };
+
 export const UNDEFINED_EXPRESSION: ExpressionEntity = {
 	deoptimizePath: () => {},
 	getLiteralValueAtPath: () => undefined,
@@ -59,6 +60,7 @@ export const UNDEFINED_EXPRESSION: ExpressionEntity = {
 	included: true,
 	toString: () => 'undefined'
 };
+
 const returnsUnknown: RawMemberDescription = {
 	value: {
 		callsArgs: null,

test/form/samples/binary-expressions/_config.js

@@ -0,0 +1,3 @@
+module.exports = {
+	description: 'handles binary expression side-effects'
+};

test/form/samples/binary-expressions/_expected.js

@@ -0,0 +1,25 @@
+if ((1 + 1).unknown) {
+	console.log('retained');
+} else {
+	console.log('retained');
+}
+console.log('retained 1');
+console.log('retained 2');
+console.log('retained 3');
+console.log('retained 4');
+console.log('retained 5');
+console.log('retained 6');
+console.log('retained 7');
+console.log('retained 8');
+console.log('retained 9');
+console.log('retained 10');
+console.log('retained 11');
+console.log('retained 12');
+console.log('retained 13');
+console.log('retained 14');
+console.log('retained 15');
+console.log('retained 16');
+console.log('retained 17');
+if (1 in 2) console.log('retained 18');
+if (1 instanceof 2) console.log('retained 19');
+console.log('retained 20');

test/form/samples/binary-expressions/main.js

@@ -0,0 +1,28 @@
+if ((1 + 1).unknown) {
+	console.log('retained');
+} else {
+	console.log('retained');
+}
+
+if (1 != '1') console.log('removed');
+if (1 !== 1) console.log('removed');
+if (4 % 2 === 0) console.log('retained 1');
+if ((6 & 3) === 2) console.log('retained 2');
+if (2 * 3 === 6) console.log('retained 3');
+if (2 ** 3 === 8) console.log('retained 4');
+if (2 + 3 === 5) console.log('retained 5');
+if (3 - 2 === 1) console.log('retained 6');
+if (6 / 3 === 2) console.log('retained 7');
+if (1 < 2 ) console.log('retained 8');
+if (3 << 1 === 6) console.log('retained 9');
+if (3 <= 4) console.log('retained 10');
+if (1 == '1') console.log('retained 11');
+if (1 === 1) console.log('retained 12');
+if (3 > 2) console.log('retained 13');
+if (3 >= 2) console.log('retained 14');
+if (6 >> 1 === 3) console.log('retained 15');
+if (-1 >>> 28 === 15) console.log('retained 16');
+if (3 ^ 5 === 6) console.log('retained 17');
+if (1 in 2) console.log('retained 18');
+if (1 instanceof 2) console.log('retained 19');
+if (2 | 4 === 6) console.log('retained 20');

test/form/samples/break-control-flow/break-statement-labels/_expected.js

@@ -31,11 +31,11 @@ outer: {
 	console.log('retained');
 }
 
-function withReturn() {
+function withConsequentReturn() {
 	outer: {
 		inner: {
-			if (globalThis.unknown) break inner;
-			else return;
+			if (globalThis.unknown) return;
+			else break inner;
 		}
 		console.log('retained');
 	}
@@ -46,4 +46,16 @@ function withReturn() {
 	}
 }
 
-withReturn();
+withConsequentReturn();
+
+function withAlternateReturn() {
+	outer: {
+		inner: {
+			if (globalThis.unknown) break inner;
+			else return;
+		}
+		console.log('retained');
+	}
+}
+
+withAlternateReturn();

test/form/samples/break-control-flow/break-statement-labels/main.js

@@ -48,11 +48,11 @@ outer: {
 	console.log('retained');
 }
 
-function withReturn() {
+function withConsequentReturn() {
 	outer: {
 		inner: {
-			if (globalThis.unknown) break inner;
-			else return;
+			if (globalThis.unknown) return;
+			else break inner;
 			console.log('removed');
 		}
 		console.log('retained');
@@ -67,4 +67,17 @@ function withReturn() {
 	}
 }
 
-withReturn();
+withConsequentReturn();
+
+function withAlternateReturn() {
+	outer: {
+		inner: {
+			if (globalThis.unknown) break inner;
+			else return;
+			console.log('removed');
+		}
+		console.log('retained');
+	}
+}
+
+withAlternateReturn();

test/form/samples/builtin-prototypes/array-expression/_config.js

@@ -1,4 +1,3 @@
 module.exports = {
-	description: 'Tree-shake known array prototype functions',
-	options: { output: { name: 'bundle' } }
+	description: 'Tree-shake known array prototype functions'
 };

test/form/samples/builtin-prototypes/array-expression/_expected.js

@@ -3,6 +3,8 @@ const map4 = [ 1 ].map( x => x ).map( x => console.log( 1 ) );
 const map5 = [ 1 ].map( x => console.log( 1 ) ).map( x => x );
 const map7 = [ 1 ].map( x => x ).map( x => x ).map( x => console.log( 1 ) );
 const map8 = [ 1 ].map( x => x ).map( x => console.log( 1 ) ).map( x => x );
+
+[]();
 const _everyEffect = [ 1 ].every( () => console.log( 1 ) || true );
 const _filterEffect = [ 1 ].filter( () => console.log( 1 ) || true );
 const _findEffect = [ 1 ].find( () => console.log( 1 ) || true );

test/form/samples/builtin-prototypes/array-expression/main.js

@@ -12,6 +12,8 @@ const map6 = [ 1 ].map( x => x ).map( x => x ).map( x => x );
 const map7 = [ 1 ].map( x => x ).map( x => x ).map( x => console.log( 1 ) );
 const map8 = [ 1 ].map( x => x ).map( x => console.log( 1 ) ).map( x => x );
 
+[]();
+
 // accessor methods
 const _includes = [].includes( 1 ).valueOf();
 const _indexOf = [].indexOf( 1 ).toPrecision( 1 );

test/form/samples/class-constructor-side-effect/_expected.js

@@ -0,0 +1,11 @@
+class Effect {
+	constructor () {
+		console.log( 'Foo' );
+	}
+}
+
+new Effect();
+
+class Empty {}
+
+new Empty.doesNotExist();

test/form/samples/class-constructor-side-effect/main.js

@@ -1,7 +1,18 @@
-class Foo {
+class Effect {
 	constructor () {
 		console.log( 'Foo' );
 	}
 }
 
-new Foo;
+new Effect();
+
+class NoEffect {
+	constructor () {
+	}
+}
+
+new NoEffect();
+
+class Empty {}
+
+new Empty.doesNotExist();

test/form/samples/side-effects-switch-statements/_expected.js

@@ -30,3 +30,7 @@ switch ( globalThis.unknown ) {
 			effect();
 	}
 }());
+
+switch ( globalThis.unknown ) {
+	case effect():
+}

test/form/samples/side-effects-switch-statements/main.js

@@ -44,3 +44,7 @@ switch ( globalThis.unknown ) {
 		default:
 	}
 }());
+
+switch ( globalThis.unknown ) {
+	case effect():
+}

test/form/samples/unary-expressions/_config.js

@@ -0,0 +1,3 @@
+module.exports = {
+	description: 'handles unary expression side-effects'
+};

test/form/samples/unary-expressions/_expected.js

@@ -0,0 +1,13 @@
+if ((!true).unknown) {
+	console.log('retained');
+} else {
+	console.log('retained');
+}
+
+console.log('retained 1');
+console.log('retained 2');
+console.log('retained 3');
+if (delete 1) console.log('retained 4');
+console.log('retained 5');
+console.log('retained 6');
+console.log('retained 7');

test/form/samples/unary-expressions/main.js

@@ -0,0 +1,13 @@
+if ((!true).unknown) {
+	console.log('retained');
+} else {
+	console.log('retained');
+}
+
+if (!false) console.log('retained 1');
+if (+'1' === 1) console.log('retained 2');
+if (-1 + 2 === 1) console.log('retained 3');
+if (delete 1) console.log('retained 4');
+if (typeof 1 === 'number') console.log('retained 5');
+if (void 1 === undefined) console.log('retained 6');
+if (~1 === -2) console.log('retained 7');

test/form/samples/undefined-var/_expected.js

@@ -1,8 +1,10 @@
 var z;
-console.log('no');
-console.log('no');
-if (z)
-	console.log('yes');
-if (!z)
-	console.log('no');
+
+console.log('retained');
+
+console.log('retained');
+
+if (z) console.log('retained');
+else console.log('retained');
+
 z = 1;