From 885835a655b4c1b3a0a9cb0f78edaa6ac446a0e7 Mon Sep 17 00:00:00 2001
From: Tal Ater <tal@talater.com>
Date: Tue, 2 Sep 2014 23:30:25 +0300
Subject: Compress conditional assignments where all possible outcomes are
 equivalant and condition has no side effects

---
 lib/compress.js               |  7 +++++++
 test/compress/conditionals.js | 44 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)

diff --git a/lib/compress.js b/lib/compress.js
index b55361b3..e493e5fe 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -2321,6 +2321,13 @@ merge(Compressor.prototype, {
                 alternative: alternative
             });
         }
+        // x=y?1:1 --> x=1
+        if (!self.condition.has_side_effects(compressor)
+            && consequent instanceof AST_Constant
+            && alternative instanceof AST_Constant
+            && consequent.equivalent_to(alternative)) {
+            return make_node_from_constant(compressor, consequent.value, self);
+        }
         return self;
     });
 
diff --git a/test/compress/conditionals.js b/test/compress/conditionals.js
index 213b246b..b0234031 100644
--- a/test/compress/conditionals.js
+++ b/test/compress/conditionals.js
@@ -232,3 +232,47 @@ cond_5: {
         some_condition() && some_other_condition() && do_something();
     }
 }
+
+cond_7: {
+    options = {
+        conditionals: true,
+        evaluate    : true
+    };
+    input: {
+        // compress these
+        if (y) {
+            x = 1+1;
+        } else {
+            x = 2;
+        }
+
+        x = y ? 'foo' : 'fo'+'o';
+
+        x = y ? 'foo' : y ? 'foo' : 'fo'+'o';
+
+        // don't compress these
+        x = y ? a : b;
+
+        x = y ? 'foo' : 'fo';
+
+        // make sure not to mess with conditions that have side effects
+        // TODO: Make sure to mess with conditions that have side effects... proprely
+        if (some_condition()) {
+            x = 1+1;
+        } else {
+            x = 2;
+        }
+
+        x = some_condition() ? 'foo' : 'fo'+'o';
+    }
+    expect: {
+        x = 2;
+        x = 'foo';
+        x = 'foo';
+        x = y ? a : b;
+        x = y ? 'foo' : 'fo';
+        x = some_condition() ? 2 : 2;
+        x = some_condition() ? 'foo' : 'foo';
+    }
+}
+
-- 
cgit v1.2.3


From 7971ed33d13d33ad2b1ebf1ddcc57c466b819514 Mon Sep 17 00:00:00 2001
From: Tal Ater <tal@talater.com>
Date: Wed, 3 Sep 2014 01:35:30 +0300
Subject: Added a test for else if

---
 test/compress/conditionals.js | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/test/compress/conditionals.js b/test/compress/conditionals.js
index b0234031..c244dc84 100644
--- a/test/compress/conditionals.js
+++ b/test/compress/conditionals.js
@@ -246,6 +246,14 @@ cond_7: {
             x = 2;
         }
 
+        if (y) {
+            x = 1+1;
+        } else if (z) {
+            x = 2;
+        } else {
+            x = 3-1;
+        }
+
         x = y ? 'foo' : 'fo'+'o';
 
         x = y ? 'foo' : y ? 'foo' : 'fo'+'o';
@@ -266,6 +274,7 @@ cond_7: {
         x = some_condition() ? 'foo' : 'fo'+'o';
     }
     expect: {
+        x = 2;
         x = 2;
         x = 'foo';
         x = 'foo';
-- 
cgit v1.2.3


From fb0ec720a4bbd3e136284c4b01a88025fbde004e Mon Sep 17 00:00:00 2001
From: Tal Ater <tal@talater.com>
Date: Thu, 4 Sep 2014 02:57:49 +0300
Subject: Compress conditions that have side effects using sequences

---
 lib/compress.js               | 10 +++++++---
 test/compress/conditionals.js | 32 ++++++++++++++++++++------------
 2 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/lib/compress.js b/lib/compress.js
index e493e5fe..77de5946 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -2322,11 +2322,15 @@ merge(Compressor.prototype, {
             });
         }
         // x=y?1:1 --> x=1
-        if (!self.condition.has_side_effects(compressor)
-            && consequent instanceof AST_Constant
+        if (consequent instanceof AST_Constant
             && alternative instanceof AST_Constant
             && consequent.equivalent_to(alternative)) {
-            return make_node_from_constant(compressor, consequent.value, self);
+            if (self.condition.has_side_effects(compressor)) {
+                return AST_Seq.from_array([self.condition, make_node_from_constant(compressor, consequent.value, self)]);
+            } else {
+                return make_node_from_constant(compressor, consequent.value, self);
+
+            }
         }
         return self;
     });
diff --git a/test/compress/conditionals.js b/test/compress/conditionals.js
index c244dc84..c20297aa 100644
--- a/test/compress/conditionals.js
+++ b/test/compress/conditionals.js
@@ -258,30 +258,38 @@ cond_7: {
 
         x = y ? 'foo' : y ? 'foo' : 'fo'+'o';
 
-        // don't compress these
-        x = y ? a : b;
-
-        x = y ? 'foo' : 'fo';
+        // Compress conditions that have side effects
+        if (condition()) {
+            x = 10+10;
+        } else {
+            x = 20;
+        }
 
-        // make sure not to mess with conditions that have side effects
-        // TODO: Make sure to mess with conditions that have side effects... proprely
-        if (some_condition()) {
-            x = 1+1;
+        if (z) {
+            x = 'fuji';
+        } else if (condition()) {
+            x = 'fu'+'ji';
         } else {
-            x = 2;
+            x = 'fuji';
         }
 
-        x = some_condition() ? 'foo' : 'fo'+'o';
+        x = condition() ? 'foobar' : 'foo'+'bar';
+
+        // don't compress these
+        x = y ? a : b;
+
+        x = y ? 'foo' : 'fo';
     }
     expect: {
         x = 2;
         x = 2;
         x = 'foo';
         x = 'foo';
+        x = (condition(), 20);
+        x = z ? 'fuji' : (condition(), 'fuji');
+        x = (condition(), 'foobar');
         x = y ? a : b;
         x = y ? 'foo' : 'fo';
-        x = some_condition() ? 2 : 2;
-        x = some_condition() ? 'foo' : 'foo';
     }
 }
 
-- 
cgit v1.2.3