block_1.9.rb in rhodes-3.2.0.beta.1

- old
+ new
@@ -1,17 +1,80 @@
-describe "Block parameters" do
-  it "does not override a shadowed variable from the outer scope" do
-    i = 0
-    a = [1,2,3]
-    a.each {|i| ;}
-    i.should == 0
+describe "Block-local variables" do
+  # Examples phrased so the concatenation of the describe and it blocks make
+  # grammatical sense.
+  it "are introduced with a semi-colon in the parameter list" do
+    lambda { [1].each {|one; bl| } }.should_not raise_error(SyntaxError)
   end
 
-  it "captures variables from the outer scope" do
-    a = [1,2,3]
-    sum = 0
-    var = nil
-    a.each {|var| sum += var}
-    sum.should == 6
-    var.should == nil
+  it "can be specified in a comma-separated list after the semi-colon" do
+    lambda { [1].each {|one; bl, bl2| } }.should_not raise_error(SyntaxError)
   end
-end
\ No newline at end of file
+
+  it "can not have the same name as one of the standard parameters" do
+    lambda { eval "[1].each {|foo; foo| }" }.should raise_error(SyntaxError)
+    lambda { eval "[1].each {|foo, bar; glark, bar| }" }.should raise_error(SyntaxError)
+  end
+
+  it "can not be prefixed with an asterisk" do
+    lambda { eval "[1].each {|foo; *bar| }" }.should raise_error(SyntaxError)
+    lambda do
+      eval "[1].each {|foo, bar; glark, *fnord| }"
+    end.should raise_error(SyntaxError)
+  end
+
+  it "can not be prefixed with an ampersand" do
+    lambda { eval "[1].each {|foo; &bar| }" }.should raise_error(SyntaxError)
+    lambda do
+      eval "[1].each {|foo, bar; glark, &fnord| }"
+    end.should raise_error(SyntaxError)
+  end
+
+  it "can not be assigned default values" do
+    lambda { eval "[1].each {|foo; bar=1| }" }.should raise_error(SyntaxError)
+    lambda do
+      eval "[1].each {|foo, bar; glark, fnord=:fnord| }"
+    end.should raise_error(SyntaxError)
+  end
+
+  it "need not be preceeded by standard parameters" do
+    lambda { [1].each {|; foo| } }.should_not raise_error(SyntaxError)
+    lambda { [1].each {|; glark, bar| } }.should_not raise_error(SyntaxError)
+  end
+
+  it "only allow a single semi-colon in the parameter list" do
+    lambda { eval "[1].each {|foo; bar; glark| }" }.should raise_error(SyntaxError)
+    lambda { eval "[1].each {|; bar; glark| }" }.should raise_error(SyntaxError)
+  end
+
+  it "override shadowed variables from the outer scope" do
+    out = :out
+    [1].each {|; out| out = :in }
+    out.should == :out
+
+    a = :a
+    b = :b
+    c = :c
+    d = :d
+    {:ant => :bee}.each_pair do |a, b; c, d|
+      a = :A
+      b = :B
+      c = :C
+      d = :D
+    end
+    a.should == :a
+    b.should == :b
+    c.should == :c
+    d.should == :d
+  end
+
+  it "are not automatically instantiated in the outer scope" do
+    defined?(glark).should be_nil
+    [1].each {|;glark| 1}
+    defined?(glark).should be_nil
+  end
+
+  it "are automatically instantiated in the block" do
+    [1].each do |;glark|
+      glark.should be_nil
+    end
+  end
+end