Test that a content change doesn't alter the ID.

evalEmpire · May 9, 2010 · 66e7266 · 66e7266
1 parent 244c92c
commit 66e7266
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Showing 2 changed files with 41 additions and 21 deletions.
diff --git a/lib/perl5i/Meta.pm b/lib/perl5i/Meta.pm
@@ -69,10 +69,11 @@ name.
 
 Returns an identifer for $object.
 
-The identifier is guaranteed to be
+The identifier is guaranteed to be:
 
   * unique to the object for the life of the process
   * a true value
+  * independent of changes to the object's contents
 
 =head2 class
 

diff --git a/t/Meta/id.t b/t/Meta/id.t
@@ -21,26 +21,45 @@ sub id_ok {
 }
 
 # Double up everything to make sure the ID is not based on content
-my @objs = (
-    bless({}, "Foo"),
-    bless({}, "Foo"),
-    qr/foo/,
-    qr/foo/,
-    sub { 42 },
-    sub { 42 },
-    \"string",
-    \"string",
-    ["foo"],
-    ["foo"],
-    42,
-    42,
-    "string",
-    "string",
-);
-
-for my $obj (@objs) {
-    my $id = id_ok( $obj );
-    is $obj->mo->id, $id, "  second call the same";
+{
+    my @objs = (
+        bless({}, "Foo"),
+        bless({}, "Foo"),
+        qr/foo/,
+        qr/foo/,
+        sub { 42 },
+        sub { 42 },
+        \"string",
+        \"string",
+        ["foo"],
+        ["foo"],
+        42,
+        42,
+        "string",
+        "string",
+    );
+
+    for my $obj (@objs) {
+        my $id = id_ok( $obj );
+        is $obj->mo->id, $id, "  second call the same";
+    }
+}
+
+
+# Test that the id is independent of content
+{
+    my $thing = 42;
+    my $id = $thing->mo->id;
+    $thing = 23;
+    is $thing->mo->id, $id, "ID remains the same for a scalar with changed content";
 }
 
+{
+    my $obj = bless {}, "Foo";
+    my $id = $obj->mo->id;
+    $obj->{key} = "value";
+    is $obj->mo->id, $id, "ID remains the same even if an object's contents change";
+}
+
+
 done_testing();