From 097bcf6a118954d60e26a2035e7702c91c17eecc Mon Sep 17 00:00:00 2001
From: Jason Jackson <jasonjckn@gmail.com>
Date: Sun, 13 May 2012 12:41:44 -0400
Subject: [PATCH][BUILD] map matching always checks for presence of key, even
 if wildcard matching on value


Signed-off-by: Jason Jackson <jasonjckn@gmail.com>
---
 src/main/clojure/clojure/core/match.clj           |   21 +++++--
 src/test/clojure/clojure/core/match/test/core.clj |   65 ++++++++++++++++++++-
 2 files changed, 78 insertions(+), 8 deletions(-)

diff --git a/src/main/clojure/clojure/core/match.clj b/src/main/clojure/clojure/core/match.clj
index 4fc0954..c595682 100644
--- a/src/main/clojure/clojure/core/match.clj
+++ b/src/main/clojure/clojure/core/match.clj
@@ -128,7 +128,10 @@
     (.valAt this k not-found)))
 
 (defn val-at*
-  ([m k] (val-at m k nil))
+  ([m k] (let [val (val-at m k ::not-found)]
+           (if (= val ::not-found)
+             (throw backtrack)
+             val)))
   ([m k not-found] (val-at m k not-found)))
 
 (defn val-at-expr [& args]
@@ -295,8 +298,8 @@
                      (conj bindings [sym bind-expr])
                      bindings)
           bindings (if (named-wildcard-pattern? p)
-                       (conj bindings [(sym p) bind-expr])
-                       bindings)]
+                     (conj bindings [(sym p) bind-expr])
+                     bindings)]
       (PatternRow. (drop-nth ps n) action
                    bindings)))
   IVecMod
@@ -849,8 +852,10 @@
 (defn ^WildcardPattern wildcard-pattern
   ([] (WildcardPattern. '_ nil))
   ([sym] 
-   {:pre [(symbol? sym)]}
-   (WildcardPattern. sym nil)))
+     {:pre [(symbol? sym)]}
+     (if (= sym '_)
+       (WildcardPattern. (gensym) nil)
+       (WildcardPattern. sym nil))))
 
 (defn wildcard-pattern? [x]
   (instance? WildcardPattern x))
@@ -1011,7 +1016,9 @@
   (to-source* [this ocr]
     (if *clojurescript*
       `(or (satisfies? cljs.core.ILookup ~ocr))
-      `(or (instance? clojure.lang.ILookup ~ocr) (satisfies? IMatchLookup ~ocr))))
+      `(or
+        (instance? clojure.lang.ILookup ~ocr)
+        (satisfies? IMatchLookup ~ocr))))
   Object
   (toString [_]
     (str m " :only " (or (:only _meta) [])))
@@ -1758,4 +1765,4 @@
   (let [bindvars# (take-nth 2 bindings)]
     `(let ~bindings
        (match [~@bindvars#]
-         ~@body))))
\ No newline at end of file
+              ~@body))))
diff --git a/src/test/clojure/clojure/core/match/test/core.clj b/src/test/clojure/clojure/core/match/test/core.clj
index 65f6165..4fc0cb1 100644
--- a/src/test/clojure/clojure/core/match/test/core.clj
+++ b/src/test/clojure/clojure/core/match/test/core.clj
@@ -76,11 +76,74 @@
   (is (= (let [x {:a 1 :b 1}]
            (match [x]
              [{:a _ :b 2}] :a0
-             [{:a 1 :c _}] :a1
+             [{:a 1 :b 1}] :a1
+             [{:c 3 :d _ :e 4}] :a2
+             :else []))
+         :a1)))
+
+(deftest map-pattern-match-2
+  (is (= (let [x {:a 1 :b 1}]
+           (match [x]
+             [{:a _ :b 1}] :a0
+             [{:a 1 :b _}] :a1
+             [{:c 3 :d _ :e 4}] :a2
+             :else []))
+         :a0)))
+
+(deftest map-pattern-match-3
+  (is (= (let [x {:a 1 :b 1 :c 1}]
+           (match [x]
+             [{:a _ :b 2}] :a0
+             [{:a 1 :b _}] :a1
+             [{:c 3 :d _ :e 4}] :a2
+             :else []))
+         :a1)))
+
+(deftest map-pattern-match-4
+  (is (= (let [x {:a 1 :b 1}]
+           (match [x]
+             [{:a _ :b 2}] :a0
+             [{:a _ :b _}] :a1
              [{:c 3 :d _ :e 4}] :a2
              :else []))
          :a1)))
 
+(deftest map-pattern-match-5
+  (is (= (let [x {:a 1}]
+           (match [x]
+             [{:a 1 :b 1}] :a0
+             [{:a _ :b _}] :a1
+             [{:c 3 :d _ :e 4}] :a2
+             :else []))
+         [])))
+
+(deftest map-pattern-match-6
+  (is (= (let [x {:a 1 :b 1}]
+           (match [x]
+             [{:b 1}] :a0
+             [{:a _ :b _}] :a1
+             [{:a _ :b _}] :a2
+             :else []))
+         :a0)))
+
+(deftest map-pattern-match-7
+  (is (= (let [x {:a 1 :b 1}]
+           (match [x]
+             [{}] :a0
+             [{:a _ :b _}] :a1
+             [{:a 1 :b 1}] :a2
+             :else []))
+         :a0)))
+
+(deftest map-pattern-match-8
+  (is (= (let [x {:a 1 :b 1}]
+           (match [x]
+             [{:x nil :y nil}] :a0
+             [{:a _ :b _}] :a1
+             [{:a 1 :b 1}] :a2
+             :else []))
+         :a1)))
+
 (deftest map-pattern-match-only-1
   (is (= (let [x {:a 1 :b 2}]
            (match [x]
-- 
1.7.4.4