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+require File.expand_path('../../spec_helper', __FILE__)
+
+# for name[, name]... in expr [do]
+# body
+# end
+describe "The for expression" do
+ it "iterates over an Enumerable passing each element to the block" do
+ j = 0
+ for i in 1..3
+ j += i
+ end
+ j.should == 6
+ end
+
+ it "iterates over a list of arrays and destructures with empty comma" do
+ for i, in [[1,2]]
+ i.should == 1
+ end
+ end
+
+ it "iterates over an Hash passing each key-value pair to the block" do
+ k = 0
+ l = 0
+
+ for i, j in { 1 => 10, 2 => 20 }
+ k += i
+ l += j
+ end
+
+ k.should == 3
+ l.should == 30
+ end
+
+ it "iterates over any object responding to 'each'" do
+ class XYZ
+ def each
+ (0..10).each { |i| yield i }
+ end
+ end
+
+ j = 0
+ for i in XYZ.new
+ j += i
+ end
+ j.should == 55
+ end
+
+ it "allows an instance variable as an iterator name" do
+ m = [1,2,3]
+ n = 0
+ for @var in m
+ n += 1
+ end
+ @var.should == 3
+ n.should == 3
+ end
+
+ it "allows a class variable as an iterator name" do
+ class OFor
+ m = [1,2,3]
+ n = 0
+ for @@var in m
+ n += 1
+ end
+ @@var.should == 3
+ n.should == 3
+ end
+ end
+
+ it "allows a constant as an iterator name" do
+ class OFor
+ m = [1,2,3]
+ n = 0
+ -> {
+ for CONST in m
+ n += 1
+ end
+ }.should complain(/already initialized constant/)
+ CONST.should == 3
+ n.should == 3
+ end
+ end
+
+ # 1.9 behaviour verified by nobu in
+ # http://redmine.ruby-lang.org/issues/show/2053
+ it "yields only as many values as there are arguments" do
+ class OFor
+ def each
+ [[1,2,3], [4,5,6]].each do |a|
+ yield(a[0],a[1],a[2])
+ end
+ end
+ end
+ o = OFor.new
+ qs = []
+ for q in o
+ qs << q
+ end
+ qs.should == [1, 4]
+ q.should == 4
+ end
+
+ it "optionally takes a 'do' after the expression" do
+ j = 0
+ for i in 1..3 do
+ j += i
+ end
+ j.should == 6
+ end
+
+ it "allows body begin on the same line if do is used" do
+ j = 0
+ for i in 1..3 do j += i
+ end
+ j.should == 6
+ end
+
+ it "executes code in containing variable scope" do
+ for i in 1..2
+ a = 123
+ end
+
+ a.should == 123
+ end
+
+ it "executes code in containing variable scope with 'do'" do
+ for i in 1..2 do
+ a = 123
+ end
+
+ a.should == 123
+ end
+
+ it "returns expr" do
+ for i in 1..3; end.should == (1..3)
+ for i,j in { 1 => 10, 2 => 20 }; end.should == { 1 => 10, 2 => 20 }
+ end
+
+ it "breaks out of a loop upon 'break', returning nil" do
+ j = 0
+ for i in 1..3
+ j += i
+
+ break if i == 2
+ end.should == nil
+
+ j.should == 3
+ end
+
+ it "allows 'break' to have an argument which becomes the value of the for expression" do
+ for i in 1..3
+ break 10 if i == 2
+ end.should == 10
+ end
+
+ it "starts the next iteration with 'next'" do
+ j = 0
+ for i in 1..5
+ next if i == 2
+
+ j += i
+ end
+
+ j.should == 13
+ end
+
+ it "repeats current iteration with 'redo'" do
+ j = 0
+ for i in 1..3
+ j += i
+
+ redo if i == 2 && j < 4
+ end
+
+ j.should == 8
+ end
+end