improve truthy compression (#3009)

test/compress/conditionals.js

@@ -703,10 +703,11 @@ ternary_boolean_alternative: {
 
 trivial_boolean_ternary_expressions : {
     options = {
+        booleans: true,
         conditionals: true,
-        evaluate    : true,
-        booleans    : true
-    };
+        evaluate: true,
+        side_effects: true,
+    }
     input: {
         f('foo' in m ? true  : false);
         f('foo' in m ? false : true);

test/compress/evaluate.js

@@ -745,7 +745,7 @@ in_boolean_context: {
             !b("foo"),
             !b([1, 2]),
             !b(/foo/),
-            ![1, foo()],
+            (foo(), !1),
             (foo(), !1)
         );
     }
@@ -1566,3 +1566,43 @@ issue_2968: {
     }
     expect_stdout: "PASS"
 }
+
+truthy_conditionals: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+    }
+    input: {
+        if (a = {}) x();
+        (b = /foo/) && y();
+        (c = function() {}) || z();
+    }
+    expect: {
+        a = {}, x();
+        b = /foo/, y();
+        c = function() {};
+    }
+}
+
+truthy_loops: {
+    options = {
+        evaluate: true,
+        loops: true,
+    }
+    input: {
+        while ([]) x();
+        do {
+            y();
+        } while(a = {});
+    }
+    expect: {
+        for (;;) {
+            [];
+            x();
+        }
+        for (;;) {
+            y();
+            a = {};
+        }
+    }
+}

test/compress/issue-1261.js

@@ -175,8 +175,8 @@ should_warn: {
         "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:141,31]",
         "WARN: Condition always true [test/compress/issue-1261.js:141,8]",
         "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:142,23]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:143,24]",
         "WARN: Condition always true [test/compress/issue-1261.js:143,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:143,24]",
         "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:144,31]",
         "WARN: Condition always false [test/compress/issue-1261.js:144,8]",
     ]

test/compress/negate-iife.js

@@ -67,7 +67,7 @@ negate_iife_3_evaluate: {
         (function(){ return true })() ? console.log(true) : console.log(false);
     }
     expect: {
-        console.log(true);
+        true, console.log(true);
     }
     expect_stdout: true
 }
@@ -110,7 +110,7 @@ negate_iife_3_off_evaluate: {
         (function(){ return true })() ? console.log(true) : console.log(false);
     }
     expect: {
-        console.log(true);
+        true, console.log(true);
     }
     expect_stdout: true
 }

test/compress/reduce_vars.js

@@ -55,7 +55,7 @@ reduce_vars: {
             console.log(a - 5);
             eval("console.log(a);");
         })(eval);
-        "yes";
+        true, "yes";
         console.log(A + 1);
     }
     expect_stdout: true
@@ -147,7 +147,7 @@ modified: {
         }
         function f4() {
             var b = 2, c = 3;
-            b = c;
+            1, b = c;
             console.log(1 + b);
             console.log(b + c);
             console.log(1 + c);
@@ -715,10 +715,12 @@ passes: {
         passes: 2,
         reduce_funcs: true,
         reduce_vars: true,
+        sequences: true,
+        side_effects: true,
         unused: true,
     }
     input: {
-        function f() {
+        (function() {
             var a = 1, b = 2, c = 3;
             if (a) {
                 b = c;
@@ -729,17 +731,22 @@ passes: {
             console.log(b + c);
             console.log(a + c);
             console.log(a + b + c);
-        }
+        })();
     }
     expect: {
-        function f() {
-            3;
-            console.log(4);
-            console.log(6);
-            console.log(4);
+        (function() {
+            console.log(4),
+            console.log(6),
+            console.log(4),
             console.log(7);
-        }
+        })();
     }
+    expect_stdout: [
+        "4",
+        "6",
+        "4",
+        "7",
+    ]
 }
 
 iife: {

test/compress/transform.js

@@ -59,7 +59,7 @@ if_else_empty: {
         if ({} ? a : b); else {}
     }
     expect: {
-        !{} ? b : a;
+        ({}), a;
     }
 }