/* * Copyright 2004 The Closure Compiler Authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.google.javascript.jscomp; /** * Tests for {@link PeepholeMinimizeConditions} in isolation. * Tests for the interaction of multiple peephole passes are in * PeepholeIntegrationTest. */ public final class PeepholeMinimizeConditionsTest extends TypeICompilerTestCase { private boolean late = true; private boolean useTypes = true; public PeepholeMinimizeConditionsTest() { super(DEFAULT_EXTERNS); } @Override public void setUp() throws Exception { super.setUp(); late = true; useTypes = true; this.mode = TypeInferenceMode.NEITHER; } @Override protected CompilerPass getProcessor(final Compiler compiler) { PeepholeOptimizationsPass peepholePass = new PeepholeOptimizationsPass( compiler, new PeepholeMinimizeConditions(late, useTypes)); peepholePass.setRetraverseOnChange(false); return peepholePass; } @Override protected int getNumRepetitions() { return 1; } @Override protected CompilerOptions getOptions() { CompilerOptions options = super.getOptions(); // NTI warns about property accesses on * options.setWarningLevel(DiagnosticGroups.NEW_CHECK_TYPES_EXTRA_CHECKS, CheckLevel.OFF); return options; } private void foldSame(String js) { testSame(js); } private void fold(String js, String expected) { test(js, expected); } /** Check that removing blocks with 1 child works */ public void testFoldOneChildBlocks() { late = false; fold("function f(){if(x)a();x=3}", "function f(){x&&a();x=3}"); fold("function f(){if(x){a()}x=3}", "function f(){x&&a();x=3}"); fold("function f(){if(x){return 3}}", "function f(){if(x)return 3}"); fold("function f(){if(x){a()}}", "function f(){x&&a()}"); fold("function f(){if(x){throw 1}}", "function f(){if(x)throw 1;}"); // Try it out with functions fold("function f(){if(x){foo()}}", "function f(){x&&foo()}"); fold("function f(){if(x){foo()}else{bar()}}", "function f(){x?foo():bar()}"); // Try it out with properties and methods fold("function f(){if(x){a.b=1}}", "function f(){if(x)a.b=1}"); fold("function f(){if(x){a.b*=1}}", "function f(){x&&(a.b*=1)}"); fold("function f(){if(x){a.b+=1}}", "function f(){x&&(a.b+=1)}"); fold("function f(){if(x){++a.b}}", "function f(){x&&++a.b}"); fold("function f(){if(x){a.foo()}}", "function f(){x&&a.foo()}"); // Try it out with throw/catch/finally [which should not change] foldSame("function f(){try{foo()}catch(e){bar(e)}finally{baz()}}"); // Try it out with switch statements foldSame("function f(){switch(x){case 1:break}}"); // Do while loops stay in a block if that's where they started foldSame("function f(){if(e1){do foo();while(e2)}else foo2()}"); // Test an obscure case with do and while fold("if(x){do{foo()}while(y)}else bar()", "if(x){do foo();while(y)}else bar()"); // Play with nested IFs fold("function f(){if(x){if(y)foo()}}", "function f(){x && (y && foo())}"); fold("function f(){if(x){if(y)foo();else bar()}}", "function f(){x&&(y?foo():bar())}"); fold("function f(){if(x){if(y)foo()}else bar()}", "function f(){x?y&&foo():bar()}"); fold("function f(){if(x){if(y)foo();else bar()}else{baz()}}", "function f(){x?y?foo():bar():baz()}"); fold("if(e1){while(e2){if(e3){foo()}}}else{bar()}", "if(e1)while(e2)e3&&foo();else bar()"); fold("if(e1){with(e2){if(e3){foo()}}}else{bar()}", "if(e1)with(e2)e3&&foo();else bar()"); fold("if(a||b){if(c||d){var x;}}", "if(a||b)if(c||d)var x"); fold("if(x){ if(y){var x;}else{var z;} }", "if(x)if(y)var x;else var z"); // NOTE - technically we can remove the blocks since both the parent // and child have elses. But we don't since it causes ambiguities in // some cases where not all descendent ifs having elses fold("if(x){ if(y){var x;}else{var z;} }else{var w}", "if(x)if(y)var x;else var z;else var w"); fold("if (x) {var x;}else { if (y) { var y;} }", "if(x)var x;else if(y)var y"); // Here's some of the ambiguous cases fold("if(a){if(b){f1();f2();}else if(c){f3();}}else {if(d){f4();}}", "if(a)if(b){f1();f2()}else c&&f3();else d&&f4()"); fold("function f(){foo()}", "function f(){foo()}"); fold("switch(x){case y: foo()}", "switch(x){case y:foo()}"); fold("try{foo()}catch(ex){bar()}finally{baz()}", "try{foo()}catch(ex){bar()}finally{baz()}"); } /** Try to minimize returns */ public void testFoldReturns() { fold("function f(){if(x)return 1;else return 2}", "function f(){return x?1:2}"); fold("function f(){if(x)return 1;return 2}", "function f(){return x?1:2}"); fold("function f(){if(x)return;return 2}", "function f(){return x?void 0:2}"); fold("function f(){if(x)return 1+x;else return 2-x}", "function f(){return x?1+x:2-x}"); fold("function f(){if(x)return 1+x;return 2-x}", "function f(){return x?1+x:2-x}"); fold("function f(){if(x)return y += 1;else return y += 2}", "function f(){return x?(y+=1):(y+=2)}"); fold("function f(){if(x)return;else return 2-x}", "function f(){if(x);else return 2-x}"); fold("function f(){if(x)return;return 2-x}", "function f(){return x?void 0:2-x}"); fold("function f(){if(x)return x;else return}", "function f(){if(x)return x;{}}"); fold("function f(){if(x)return x;return}", "function f(){if(x)return x}"); foldSame("function f(){for(var x in y) { return x.y; } return k}"); } public void testCombineIfs1() { fold("function f() {if (x) return 1; if (y) return 1}", "function f() {if (x||y) return 1;}"); fold("function f() {if (x) return 1; if (y) foo(); else return 1}", "function f() {if ((!x)&&y) foo(); else return 1;}"); } public void testCombineIfs2() { // combinable but not yet done foldSame("function f() {if (x) throw 1; if (y) throw 1}"); // Can't combine, side-effect fold("function f(){ if (x) g(); if (y) g() }", "function f(){ x&&g(); y&&g() }"); // Can't combine, side-effect fold("function f(){ if (x) y = 0; if (y) y = 0; }", "function f(){ x&&(y = 0); y&&(y = 0); }"); } public void testCombineIfs3() { foldSame("function f() {if (x) return 1; if (y) {g();f()}}"); } /** Try to minimize assignments */ public void testFoldAssignments() { fold("function f(){if(x)y=3;else y=4;}", "function f(){y=x?3:4}"); fold("function f(){if(x)y=1+a;else y=2+a;}", "function f(){y=x?1+a:2+a}"); // and operation assignments fold("function f(){if(x)y+=1;else y+=2;}", "function f(){y+=x?1:2}"); fold("function f(){if(x)y-=1;else y-=2;}", "function f(){y-=x?1:2}"); fold("function f(){if(x)y%=1;else y%=2;}", "function f(){y%=x?1:2}"); fold("function f(){if(x)y|=1;else y|=2;}", "function f(){y|=x?1:2}"); // sanity check, don't fold if the 2 ops don't match foldSame("function f(){x ? y-=1 : y+=2}"); // sanity check, don't fold if the 2 LHS don't match foldSame("function f(){x ? y-=1 : z-=1}"); // sanity check, don't fold if there are potential effects foldSame("function f(){x ? y().a=3 : y().a=4}"); } public void testRemoveDuplicateStatements() { fold("if (a) { x = 1; x++ } else { x = 2; x++ }", "x=(a) ? 1 : 2; x++"); fold("if (a) { x = 1; x++; y += 1; z = pi; }" + " else { x = 2; x++; y += 1; z = pi; }", "x=(a) ? 1 : 2; x++; y += 1; z = pi;"); fold("function z() {" + "if (a) { foo(); return !0 } else { goo(); return !0 }" + "}", "function z() {(a) ? foo() : goo(); return !0}"); fold("function z() {if (a) { foo(); x = true; return true " + "} else { goo(); x = true; return true }}", "function z() {(a) ? foo() : goo(); x = true; return true}"); fold("function z() {" + " if (a) { bar(); foo(); return true }" + " else { bar(); goo(); return true }" + "}", "function z() {" + " if (a) { bar(); foo(); }" + " else { bar(); goo(); }" + " return true;" + "}"); } public void testNotCond() { fold("function f(){if(!x)foo()}", "function f(){x||foo()}"); fold("function f(){if(!x)b=1}", "function f(){x||(b=1)}"); fold("if(!x)z=1;else if(y)z=2", "if(x){y&&(z=2);}else{z=1;}"); fold("if(x)y&&(z=2);else z=1;", "x ? y&&(z=2) : z=1"); fold("function f(){if(!(x=1))a.b=1}", "function f(){(x=1)||(a.b=1)}"); } public void testAndParenthesesCount() { fold("function f(){if(x||y)a.foo()}", "function f(){(x||y)&&a.foo()}"); fold("function f(){if(x.a)x.a=0}", "function f(){x.a&&(x.a=0)}"); foldSame("function f(){if(x()||y()){x()||y()}}"); } public void testFoldLogicalOpStringCompare() { // side-effects // There is two way to parse two &&'s and both are correct. fold("if (foo() && false) z()", "(foo(), 0) && z()"); } public void testFoldNot() { fold("while(!(x==y)){a=b;}" , "while(x!=y){a=b;}"); fold("while(!(x!=y)){a=b;}" , "while(x==y){a=b;}"); fold("while(!(x===y)){a=b;}", "while(x!==y){a=b;}"); fold("while(!(x!==y)){a=b;}", "while(x===y){a=b;}"); // Because !(x<NaN) != x>=NaN don't fold < and > cases. foldSame("while(!(x>y)){a=b;}"); foldSame("while(!(x>=y)){a=b;}"); foldSame("while(!(x<y)){a=b;}"); foldSame("while(!(x<=y)){a=b;}"); foldSame("while(!(x<=NaN)){a=b;}"); // NOT forces a boolean context fold("x = !(y() && true)", "x = !y()"); // This will be further optimized by PeepholeFoldConstants. fold("x = !true", "x = !1"); } public void testMinimizeExprCondition() { fold("(x ? true : false) && y()", "x&&y()"); fold("(x ? false : true) && y()", "(!x)&&y()"); fold("(x ? true : y) && y()", "(x || y)&&y()"); fold("(x ? y : false) && y()", "(x && y)&&y()"); fold("(x && true) && y()", "x && y()"); fold("(x && false) && y()", "0&&y()"); fold("(x || true) && y()", "1&&y()"); fold("(x || false) && y()", "x&&y()"); } public void testMinimizeWhileCondition() { // This test uses constant folding logic, so is only here for completeness. fold("while(!!true) foo()", "while(1) foo()"); // These test tryMinimizeCondition fold("while(!!x) foo()", "while(x) foo()"); fold("while(!(!x&&!y)) foo()", "while(x||y) foo()"); fold("while(x||!!y) foo()", "while(x||y) foo()"); fold("while(!(!!x&&y)) foo()", "while(!x||!y) foo()"); fold("while(!(!x&&y)) foo()", "while(x||!y) foo()"); fold("while(!(x||!y)) foo()", "while(!x&&y) foo()"); fold("while(!(x||y)) foo()", "while(!x&&!y) foo()"); fold("while(!(!x||y-z)) foo()", "while(x&&!(y-z)) foo()"); fold("while(!(!(x/y)||z+w)) foo()", "while(x/y&&!(z+w)) foo()"); foldSame("while(!(x+y||z)) foo()"); foldSame("while(!(x&&y*z)) foo()"); fold("while(!(!!x&&y)) foo()", "while(!x||!y) foo()"); fold("while(x&&!0) foo()", "while(x) foo()"); fold("while(x||!1) foo()", "while(x) foo()"); fold("while(!((x,y)&&z)) foo()", "while((x,!y)||!z) foo()"); } public void testMinimizeDemorganRemoveLeadingNot() { fold("if(!(!a||!b)&&c) foo()", "((a&&b)&&c)&&foo()"); fold("if(!(x&&y)) foo()", "x&&y||foo()"); fold("if(!(x||y)) foo()", "(x||y)||foo()"); } public void testMinimizeDemorgan1() { fold("if(!a&&!b)foo()", "(a||b)||foo()"); } public void testMinimizeDemorgan3() { fold("if((!a||!b)&&(c||d)) foo()", "(a&&b||!c&&!d)||foo()"); } public void testMinimizeDemorgan5() { fold("if((!a||!b)&&c) foo()", "(a&&b||!c)||foo()"); } public void testMinimizeDemorgan11() { fold("if (x && (y===2 || !f()) && (y===3 || !h())) foo()", "(!x || y!==2 && f() || y!==3 && h()) || foo()"); } public void testMinimizeDemorgan20() { fold("if (0===c && (2===a || 1===a)) f(); else g()", "if (0!==c || 2!==a && 1!==a) g(); else f()"); fold("if (0!==c || 2!==a && 1!==a) g(); else f()", "(0!==c || 2!==a && 1!==a) ? g() : f()"); } public void testPreserveIf() { foldSame("if(!a&&!b)for(;f(););"); } public void testNoSwapWithDanglingElse() { foldSame("if(!x) {for(;;)foo(); for(;;)bar()} else if(y) for(;;) f()"); foldSame("if(!a&&!b) {for(;;)foo(); for(;;)bar()} else if(y) for(;;) f()"); } public void testMinimizeHook() { fold("x ? x : y", "x || y"); // We assume GETPROPs don't have side effects. fold("x.y ? x.y : x.z", "x.y || x.z"); // This can be folded if x() does not have side effects. foldSame("x() ? x() : y()"); fold("!x ? foo() : bar()", "x ? bar() : foo()"); fold("while(!(x ? y : z)) foo();", "while(x ? !y : !z) foo();"); fold("(x ? !y : !z) ? foo() : bar()", "(x ? y : z) ? bar() : foo()"); } public void testMinimizeComma() { fold("while(!(inc(), test())) foo();", "while(inc(), !test()) foo();"); fold("(inc(), !test()) ? foo() : bar()", "(inc(), test()) ? bar() : foo()"); } public void testMinimizeExprResult() { fold("!x||!y", "x&&y"); fold("if(!(x&&!y)) foo()", "x&&!y||!foo()"); fold("if(!x||y) foo()", "x&&!y||!foo()"); } public void testMinimizeDemorgan21() { fold("if (0===c && (2===a || 1===a)) f()", "(0!==c || 2!==a && 1!==a) || f()"); } public void testMinimizeAndOr1() { fold("if ((!a || !b) && (d || e)) f()", "(a&&b || !d&&!e) || f()"); } public void testMinimizeForCondition() { // This test uses constant folding logic, so is only here for completeness. // These could be simplified to "for(;;) ..." fold("for(;!!true;) foo()", "for(;1;) foo()"); // Don't bother with FOR inits as there are normalized out. fold("for(!!true;;) foo()", "for(!0;;) foo()"); // These test tryMinimizeCondition fold("for(;!!x;) foo()", "for(;x;) foo()"); // sanity check foldSame("for(a in b) foo()"); foldSame("for(a in {}) foo()"); foldSame("for(a in []) foo()"); fold("for(a in !!true) foo()", "for(a in !0) foo()"); } public void testMinimizeCondition_example1() { // Based on a real failing code sample. fold("if(!!(f() > 20)) {foo();foo()}", "if(f() > 20){foo();foo()}"); } public void testFoldLoopBreakLate() { late = true; fold("for(;;) if (a) break", "for(;!a;);"); foldSame("for(;;) if (a) { f(); break }"); fold("for(;;) if (a) break; else f()", "for(;!a;) { { f(); } }"); fold("for(;a;) if (b) break", "for(;a && !b;);"); fold("for(;a;) { if (b) break; if (c) break; }", "for(;(a && !b);) if (c) break;"); fold("for(;(a && !b);) if (c) break;", "for(;(a && !b) && !c;);"); fold("for(;;) { if (foo) { break; var x; } } x;", "var x; for(;!foo;) {} x;"); // 'while' is normalized to 'for' enableNormalize(); fold("while(true) if (a) break", "for(;1&&!a;);"); disableNormalize(); } public void testFoldLoopBreakEarly() { late = false; foldSame("for(;;) if (a) break"); foldSame("for(;;) if (a) { f(); break }"); foldSame("for(;;) if (a) break; else f()"); foldSame("for(;a;) if (b) break"); foldSame("for(;a;) { if (b) break; if (c) break; }"); foldSame("while(1) if (a) break"); enableNormalize(); foldSame("while(1) if (a) break"); disableNormalize(); } public void testFoldConditionalVarDeclaration() { fold("if(x) var y=1;else y=2", "var y=x?1:2"); fold("if(x) y=1;else var y=2", "var y=x?1:2"); foldSame("if(x) var y = 1; z = 2"); foldSame("if(x||y) y = 1; var z = 2"); foldSame("if(x) { var y = 1; print(y)} else y = 2 "); foldSame("if(x) var y = 1; else {y = 2; print(y)}"); } public void testFoldIfWithLowerOperatorsInside() { fold("if (x + (y=5)) z && (w,z);", "x + (y=5) && (z && (w,z))"); fold("if (!(x+(y=5))) z && (w,z);", "x + (y=5) || z && (w,z)"); fold("if (x + (y=5)) if (z && (w,z)) for(;;) foo();", "if (x + (y=5) && (z && (w,z))) for(;;) foo();"); } public void testSubsituteReturn() { fold("function f() { while(x) { return }}", "function f() { while(x) { break }}"); foldSame("function f() { while(x) { return 5 } }"); foldSame("function f() { a: { return 5 } }"); fold("function f() { while(x) { return 5} return 5}", "function f() { while(x) { break } return 5}"); fold("function f() { while(x) { return x} return x}", "function f() { while(x) { break } return x}"); fold("function f() { while(x) { if (y) { return }}}", "function f() { while(x) { if (y) { break }}}"); fold("function f() { while(x) { if (y) { return }} return}", "function f() { while(x) { if (y) { break }}}"); fold("function f() { while(x) { if (y) { return 5 }} return 5}", "function f() { while(x) { if (y) { break }} return 5}"); // It doesn't matter if x is changed between them. We are still returning // x at whatever x value current holds. The whole x = 1 is skipped. fold("function f() { while(x) { if (y) { return x } x = 1} return x}", "function f() { while(x) { if (y) { break } x = 1} return x}"); // RemoveUnreachableCode would take care of the useless breaks. fold("function f() { while(x) { if (y) { return x } return x} return x}", "function f() { while(x) { if (y) {} break }return x}"); // A break here only breaks out of the inner loop. foldSame("function f() { while(x) { while (y) { return } } }"); foldSame("function f() { while(1) { return 7} return 5}"); foldSame("function f() {" + " try { while(x) {return f()}} catch (e) { } return f()}"); foldSame("function f() {" + " try { while(x) {return f()}} finally {alert(1)} return f()}"); // Both returns has the same handler fold("function f() {" + " try { while(x) { return f() } return f() } catch (e) { } }", "function f() {" + " try { while(x) { break } return f() } catch (e) { } }"); // We can't fold this because it'll change the order of when foo is called. foldSame("function f() {" + " try { while(x) { return foo() } } finally { alert(1) } " + " return foo()}"); // This is fine, we have no side effect in the return value. fold("function f() {" + " try { while(x) { return 1 } } finally { alert(1) } return 1}", "function f() {" + " try { while(x) { break } } finally { alert(1) } return 1}" ); foldSame("function f() { try{ return a } finally { a = 2 } return a; }"); fold( "function f() { switch(a){ case 1: return a; default: g();} return a;}", "function f() { switch(a){ case 1: break; default: g();} return a; }"); } public void testSubsituteBreakForThrow() { foldSame("function f() { while(x) { throw Error }}"); fold("function f() { while(x) { throw Error } throw Error }", "function f() { while(x) { break } throw Error}"); foldSame("function f() { while(x) { throw Error(1) } throw Error(2)}"); foldSame("function f() { while(x) { throw Error(1) } return Error(2)}"); foldSame("function f() { while(x) { throw 5 } }"); foldSame("function f() { a: { throw 5 } }"); fold("function f() { while(x) { throw 5} throw 5}", "function f() { while(x) { break } throw 5}"); fold("function f() { while(x) { throw x} throw x}", "function f() { while(x) { break } throw x}"); foldSame("function f() { while(x) { if (y) { throw Error }}}"); fold("function f() { while(x) { if (y) { throw Error }} throw Error}", "function f() { while(x) { if (y) { break }} throw Error}"); fold("function f() { while(x) { if (y) { throw 5 }} throw 5}", "function f() { while(x) { if (y) { break }} throw 5}"); // It doesn't matter if x is changed between them. We are still throwing // x at whatever x value current holds. The whole x = 1 is skipped. fold("function f() { while(x) { if (y) { throw x } x = 1} throw x}", "function f() { while(x) { if (y) { break } x = 1} throw x}"); // RemoveUnreachableCode would take care of the useless breaks. fold("function f() { while(x) { if (y) { throw x } throw x} throw x}", "function f() { while(x) { if (y) {} break }throw x}"); // A break here only breaks out of the inner loop. foldSame("function f() { while(x) { while (y) { throw Error } } }"); foldSame("function f() { while(1) { throw 7} throw 5}"); foldSame("function f() {" + " try { while(x) {throw f()}} catch (e) { } throw f()}"); foldSame("function f() {" + " try { while(x) {throw f()}} finally {alert(1)} throw f()}"); // Both throws has the same handler fold("function f() {" + " try { while(x) { throw f() } throw f() } catch (e) { } }", "function f() {" + " try { while(x) { break } throw f() } catch (e) { } }"); // We can't fold this because it'll change the order of when foo is called. foldSame("function f() {" + " try { while(x) { throw foo() } } finally { alert(1) } " + " throw foo()}"); // This is fine, we have no side effect in the throw value. fold("function f() {" + " try { while(x) { throw 1 } } finally { alert(1) } throw 1}", "function f() {" + " try { while(x) { break } } finally { alert(1) } throw 1}" ); foldSame("function f() { try{ throw a } finally { a = 2 } throw a; }"); fold( "function f() { switch(a){ case 1: throw a; default: g();} throw a;}", "function f() { switch(a){ case 1: break; default: g();} throw a; }"); } public void testRemoveDuplicateReturn() { fold("function f() { return; }", "function f(){}"); foldSame("function f() { return a; }"); fold("function f() { if (x) { return a } return a; }", "function f() { if (x) {} return a; }"); foldSame( "function f() { try { if (x) { return a } } catch(e) {} return a; }"); foldSame( "function f() { try { if (x) {} } catch(e) {} return 1; }"); // finally clauses may have side effects foldSame( "function f() { try { if (x) { return a } } finally { a++ } return a; }"); // but they don't matter if the result doesn't have side effects and can't // be affect by side-effects. fold("function f() { try { if (x) { return 1 } } finally {} return 1; }", "function f() { try { if (x) {} } finally {} return 1; }"); fold("function f() { switch(a){ case 1: return a; } return a; }", "function f() { switch(a){ case 1: } return a; }"); fold("function f() { switch(a){ " + " case 1: return a; case 2: return a; } return a; }", "function f() { switch(a){ " + " case 1: break; case 2: } return a; }"); } public void testRemoveDuplicateThrow() { foldSame("function f() { throw a; }"); fold("function f() { if (x) { throw a } throw a; }", "function f() { if (x) {} throw a; }"); foldSame( "function f() { try { if (x) {throw a} } catch(e) {} throw a; }"); foldSame( "function f() { try { if (x) {throw 1} } catch(e) {f()} throw 1; }"); foldSame( "function f() { try { if (x) {throw 1} } catch(e) {f()} throw 1; }"); foldSame( "function f() { try { if (x) {throw 1} } catch(e) {throw 1}}"); fold( "function f() { try { if (x) {throw 1} } catch(e) {throw 1} throw 1; }", "function f() { try { if (x) {throw 1} } catch(e) {} throw 1; }"); // finally clauses may have side effects foldSame( "function f() { try { if (x) { throw a } } finally { a++ } throw a; }"); // but they don't matter if the result doesn't have side effects and can't // be affect by side-effects. fold("function f() { try { if (x) { throw 1 } } finally {} throw 1; }", "function f() { try { if (x) {} } finally {} throw 1; }"); fold("function f() { switch(a){ case 1: throw a; } throw a; }", "function f() { switch(a){ case 1: } throw a; }"); fold("function f() { switch(a){ " + "case 1: throw a; case 2: throw a; } throw a; }", "function f() { switch(a){ case 1: break; case 2: } throw a; }"); } public void testNestedIfCombine() { fold("if(x)if(y){while(1){}}", "if(x&&y){while(1){}}"); fold("if(x||z)if(y){while(1){}}", "if((x||z)&&y){while(1){}}"); fold("if(x)if(y||z){while(1){}}", "if((x)&&(y||z)){while(1){}}"); foldSame("if(x||z)if(y||z){while(1){}}"); fold("if(x)if(y){if(z){while(1){}}}", "if(x&&(y&&z)){while(1){}}"); } public void testIssue291() { fold("if (true) { f.onchange(); }", "if (1) f.onchange();"); foldSame("if (f) { f.onchange(); }"); foldSame("if (f) { f.bar(); } else { f.onchange(); }"); fold("if (f) { f.bonchange(); }", "f && f.bonchange();"); foldSame("if (f) { f['x'](); }"); } public void testObjectLiteral() { test("({})", "1"); test("({a:1})", "1"); testSame("({a:foo()})"); testSame("({'a':foo()})"); } public void testArrayLiteral() { test("([])", "1"); test("([1])", "1"); test("([a])", "1"); testSame("([foo()])"); } public void testRemoveElseCause() { test("function f() {" + " if(x) return 1;" + " else if(x) return 2;" + " else if(x) return 3 }", "function f() {" + " if(x) return 1;" + "{ if(x) return 2;" + "{ if(x) return 3 } } }"); } public void testRemoveElseCause1() { test("function f() { if (x) throw 1; else f() }", "function f() { if (x) throw 1; { f() } }"); } public void testRemoveElseCause2() { test("function f() { if (x) return 1; else f() }", "function f() { if (x) return 1; { f() } }"); test("function f() { if (x) return; else f() }", "function f() { if (x) {} else { f() } }"); // This case is handled by minimize exit points. testSame("function f() { if (x) return; f() }"); } public void testRemoveElseCause3() { testSame("function f() { a:{if (x) break a; else f() } }"); testSame("function f() { if (x) { a:{ break a } } else f() }"); testSame("function f() { if (x) a:{ break a } else f() }"); } public void testRemoveElseCause4() { testSame("function f() { if (x) { if (y) { return 1; } } else f() }"); } public void testIssue925() { test( "if (x[--y] === 1) {\n" + " x[y] = 0;\n" + "} else {\n" + " x[y] = 1;\n" + "}", "(x[--y] === 1) ? x[y] = 0 : x[y] = 1;"); test( "if (x[--y]) {\n" + " a = 0;\n" + "} else {\n" + " a = 1;\n" + "}", "a = (x[--y]) ? 0 : 1;"); test("if (x++) { x += 2 } else { x += 3 }", "x++ ? x += 2 : x += 3"); test("if (x++) { x = x + 2 } else { x = x + 3 }", "x = x++ ? x + 2 : x + 3"); } public void testCoercionSubstitution_disabled() { this.mode = TypeInferenceMode.BOTH; useTypes = false; testSame("var x = {}; if (x != null) throw 'a';"); testSame("var x = {}; var y = x != null;"); testSame("var x = 1; if (x != 0) throw 'a';"); testSame("var x = 1; var y = x != 0;"); } public void testCoercionSubstitution_booleanResult() { this.mode = TypeInferenceMode.BOTH; test("var x = {}; var y = x != null;", "var x = {}; var y = !!x;"); test("var x = {}; var y = x == null;", "var x = {}; var y = !x;"); testSame("var x = {}; var y = x !== null;"); testSame("var x = undefined; var y = x !== null;"); testSame("var x = {}; var y = x === null;"); testSame("var x = undefined; var y = x === null;"); test("var x = 1; var y = x != 0;", "var x = 1; var y = !!x;"); test("var x = 1; var y = x == 0;", "var x = 1; var y = !x;"); test("var x = 1; var y = x !== 0;", "var x = 1; var y = !!x;"); test("var x = 1; var y = x === 0;", "var x = 1; var y = !x;"); } public void testCoercionSubstitution_if() { this.mode = TypeInferenceMode.BOTH; test("var x = {};\nif (x != null) throw 'a';\n", "var x = {};\nif (x) throw 'a';\n"); test("var x = {};\nif (x == null) throw 'a';\n", "var x = {};\nif (!x) throw 'a';\n"); testSame("var x = {};\nif (x !== null) throw 'a';\n"); testSame("var x = {};\nif (x === null) throw 'a';\n"); test("var x = {};\nif (null != x) throw 'a';\n", "var x = {};\nif (x) throw 'a';\n"); test("var x = {};\nif (null == x) throw 'a';\n", "var x = {};\nif (!x) throw 'a';\n"); testSame("var x = {};\nif (null !== x) throw 'a';\n"); testSame("var x = {};\nif (null === x) throw 'a';\n"); test("var x = 1;\nif (x != 0) throw 'a';\n", "var x = 1;\nif (x) throw 'a';\n"); test("var x = 1;\nif (x == 0) throw 'a';\n", "var x = 1;\nif (!x) throw 'a';\n"); test("var x = 1;\nif (x !== 0) throw 'a';\n", "var x = 1;\nif (x) throw 'a';\n"); test("var x = 1;\nif (x === 0) throw 'a';\n", "var x = 1;\nif (!x) throw 'a';\n"); test("var x = 1;\nif (0 != x) throw 'a';\n", "var x = 1;\nif (x) throw 'a';\n"); test("var x = 1;\nif (0 == x) throw 'a';\n", "var x = 1;\nif (!x) throw 'a';\n"); test("var x = 1;\nif (0 !== x) throw 'a';\n", "var x = 1;\nif (x) throw 'a';\n"); test("var x = 1;\nif (0 === x) throw 'a';\n", "var x = 1;\nif (!x) throw 'a';\n"); } public void testCoercionSubstitution_expression() { this.mode = TypeInferenceMode.BOTH; test( "var x = {}; x != null && alert('b');", "var x = {}; x && alert('b');"); test( "var x = 1; x != 0 && alert('b');", "var x = 1; x && alert('b');"); } public void testCoercionSubstitution_hook() { this.mode = TypeInferenceMode.BOTH; test("var x = {};\nvar y = x != null ? 1 : 2;\n", "var x = {};\nvar y = x ? 1 : 2;\n"); test("var x = 1;\nvar y = x != 0 ? 1 : 2;\n", "var x = 1;\nvar y = x ? 1 : 2;\n"); } public void testCoercionSubstitution_not() { this.mode = TypeInferenceMode.BOTH; test("var x = {};\nvar y = !(x != null) ? 1 : 2;\n", "var x = {};\nvar y = x ? 2 : 1;\n"); test("var x = 1;\nvar y = !(x != 0) ? 1 : 2;\n", "var x = 1;\nvar y = x ? 2 : 1;\n"); } public void testCoercionSubstitution_while() { this.mode = TypeInferenceMode.BOTH; test("var x = {};\nwhile (x != null) throw 'a'\n", "var x = {};\nwhile (x) throw 'a';\n"); test("var x = 1;\nwhile (x != 0) throw 'a'\n", "var x = 1;\nwhile (x) throw 'a';\n"); } public void testCoercionSubstitution_nullableType() { this.mode = TypeInferenceMode.BOTH; test( "var x = /** @type {?Object} */ ({}); if (x != null) throw 'a';", "var x = /** @type {?Object} */ ({}); if (x) throw 'a';"); // We back off on strict comparison against null. testSame("var x = /** @type {?Object} */ ({}); if (x !== null) throw 'a';"); test( "var x = /** @type {?Object} */ ({}); if (x != undefined) throw 'a';", "var x = /** @type {?Object} */ ({}); if (x) throw 'a';"); testSame("var x = /** @type {?Object} */ ({}); if (x !== undefined) throw 'a';"); test( "var x = /** @type {!Object|undefined} */ ({}); if (x !== undefined) throw 'a';", "var x = /** @type {!Object|undefined} */ ({}); if (x) throw 'a';"); testSame("var x = /** @type {!Object|undefined} */ ({}); if (x !== null) throw 'a';"); testSame("var x = /** @type {?number} */ (1); if (x != 0) throw 'a';"); testSame("var x = /** @type {?string} */ (''); if (x != null) throw 'a';"); testSame("var x = /** @type {?boolean} */ (true); if (x != null) throw 'a';"); testSame(LINE_JOINER.join( "/** @enum {string} */", "var E = { F: '1' };", "/** @param {?E} x */", "function f(x) {", " if (x != null) throw 'a';", "}")); testSame(LINE_JOINER.join( "/** @enum {number} */", "var E1 = { F: 1 };", "/** @enum {number} */", "var E2 = { F: 1 };", "/** @param {?E1|?E2} x */", "function f(x) {", " if (x != null) throw 'a';", "}")); test(LINE_JOINER.join( "/** @enum {Object} */", "var E = { F: {} };", "/** @param {?E} x */", "function f(x) {", " if (x != null) throw 'a';", "}"), LINE_JOINER.join( "/** @enum {Object} */", "var E = { F: {} };", "/** @param {?E} x */", "function f(x) {", " if (x) throw 'a';", "}")); test( "if (/** @type {Array|undefined} */ (window['c']) == null) {}", "if (!/** @type {Array|undefined} */ (window['c'])) {}"); testSame("if (/** @type {Array|undefined} */ (window['c']) === null) {}"); } public void testCoercionSubstitution_unknownType() { this.mode = TypeInferenceMode.BOTH; testSame("var x = /** @type {?} */ ({});\nif (x != null) throw 'a';\n"); testSame("var x = /** @type {?} */ (1);\nif (x != 0) throw 'a';\n"); } public void testCoercionSubstitution_allType() { this.mode = TypeInferenceMode.BOTH; testSame("var x = /** @type {*} */ ({});\nif (x != null) throw 'a';\n"); testSame("var x = /** @type {*} */ (1);\nif (x != 0) throw 'a';\n"); } public void testCoercionSubstitution_primitivesVsNull() { this.mode = TypeInferenceMode.BOTH; testSame("var x = 0;\nif (x != null) throw 'a';\n"); testSame("var x = '';\nif (x != null) throw 'a';\n"); testSame("var x = false;\nif (x != null) throw 'a';\n"); } public void testCoercionSubstitution_nonNumberVsZero() { this.mode = TypeInferenceMode.BOTH; testSame("var x = {};\nif (x != 0) throw 'a';\n"); testSame("var x = '';\nif (x != 0) throw 'a';\n"); testSame("var x = false;\nif (x != 0) throw 'a';\n"); } public void testCoercionSubstitution_boxedNumberVsZero() { this.mode = TypeInferenceMode.BOTH; testSame("var x = new Number(0);\nif (x != 0) throw 'a';\n"); } public void testCoercionSubstitution_boxedPrimitives() { this.mode = TypeInferenceMode.BOTH; test( "var x = new Number();\nif (x != null) throw 'a';\n", "var x = new Number();\nif (x) throw 'a';\n"); test( "var x = new String();\nif (x != null) throw 'a';\n", "var x = new String();\nif (x) throw 'a';\n"); test( "var x = new Boolean();\nif (x != null) throw 'a';\n", "var x = new Boolean();\nif (x) throw 'a';\n"); } }