14 files changed, 149 insertions, 33 deletions
diff --git a/spec/ruby/core/env/assoc_spec.rb b/spec/ruby/core/env/assoc_spec.rb
index 9946e328a9..c7a388db75 100644
--- a/spec/ruby/core/env/assoc_spec.rb
+++ b/spec/ruby/core/env/assoc_spec.rb
@@ -26,6 +26,6 @@ describe "ENV.assoc" do
   end
 
   it "raises TypeError if the argument is not a String and does not respond to #to_str" do
-    -> { ENV.assoc(Object.new) }.should raise_error(TypeError)
+    -> { ENV.assoc(Object.new) }.should raise_error(TypeError, "no implicit conversion of Object into String")
   end
 end
diff --git a/spec/ruby/core/env/delete_spec.rb b/spec/ruby/core/env/delete_spec.rb
index e875df4aeb..b7fe1ee675 100644
--- a/spec/ruby/core/env/delete_spec.rb
+++ b/spec/ruby/core/env/delete_spec.rb
@@ -30,6 +30,12 @@ describe "ENV.delete" do
     ScratchPad.recorded.should == "foo"
   end
 
+  it "does not evaluate the block if the envirionment variable exists" do
+    ENV["foo"] = "bar"
+    ENV.delete("foo") { |name| fail "Should not happen" }
+    ENV["foo"].should == nil
+  end
+
   it "raises TypeError if the argument is not a String and does not respond to #to_str" do
     -> { ENV.delete(Object.new) }.should raise_error(TypeError, "no implicit conversion of Object into String")
   end
diff --git a/spec/ruby/core/env/each_key_spec.rb b/spec/ruby/core/env/each_key_spec.rb
index 5c5cf4f80e..0efcb09900 100644
--- a/spec/ruby/core/env/each_key_spec.rb
+++ b/spec/ruby/core/env/each_key_spec.rb
@@ -10,7 +10,7 @@ describe "ENV.each_key" do
       ENV.clear
       ENV["1"] = "3"
       ENV["2"] = "4"
-      ENV.each_key { |k| e << k }
+      ENV.each_key { |k| e << k }.should equal(ENV)
       e.should include("1")
       e.should include("2")
     ensure
diff --git a/spec/ruby/core/env/each_value_spec.rb b/spec/ruby/core/env/each_value_spec.rb
index ea29b3a0d7..60d9f605d8 100644
--- a/spec/ruby/core/env/each_value_spec.rb
+++ b/spec/ruby/core/env/each_value_spec.rb
@@ -10,7 +10,7 @@ describe "ENV.each_value" do
       ENV.clear
       ENV["1"] = "3"
       ENV["2"] = "4"
-      ENV.each_value { |v| e << v }
+      ENV.each_value { |v| e << v }.should equal(ENV)
       e.should include("3")
       e.should include("4")
     ensure
diff --git a/spec/ruby/core/env/index_spec.rb b/spec/ruby/core/env/index_spec.rb
index 04986a0421..43875f5a50 100644
--- a/spec/ruby/core/env/index_spec.rb
+++ b/spec/ruby/core/env/index_spec.rb
@@ -3,4 +3,10 @@ require_relative 'shared/key'
 
 describe "ENV.index" do
   it_behaves_like :env_key, :index
+
+  it "warns about deprecation" do
+    -> do
+      ENV.index("foo")
+    end.should complain(/warning: ENV.index is deprecated; use ENV.key/)
+  end
 end
diff --git a/spec/ruby/core/env/keys_spec.rb b/spec/ruby/core/env/keys_spec.rb
index 3699b2c225..b074a8f7c7 100644
--- a/spec/ruby/core/env/keys_spec.rb
+++ b/spec/ruby/core/env/keys_spec.rb
@@ -2,8 +2,8 @@ require_relative '../../spec_helper'
 
 describe "ENV.keys" do
 
-  it "returns all the keys" do
-    ENV.keys.sort.should == ENV.to_hash.keys.sort
+  it "returns an array of the keys" do
+    ENV.keys.should == ENV.to_hash.keys
   end
 
   it "returns the keys in the locale encoding" do
diff --git a/spec/ruby/core/env/rehash_spec.rb b/spec/ruby/core/env/rehash_spec.rb
index e724feaa39..3782e4b727 100644
--- a/spec/ruby/core/env/rehash_spec.rb
+++ b/spec/ruby/core/env/rehash_spec.rb
@@ -1 +1,7 @@
 require_relative '../../spec_helper'
+
+describe "ENV.rehash" do
+  it "returns nil" do
+    ENV.rehash.should == nil
+  end
+end
diff --git a/spec/ruby/core/env/replace_spec.rb b/spec/ruby/core/env/replace_spec.rb
index 8837deea4a..9fc67643d1 100644
--- a/spec/ruby/core/env/replace_spec.rb
+++ b/spec/ruby/core/env/replace_spec.rb
@@ -1,15 +1,51 @@
 require_relative '../../spec_helper'
 
 describe "ENV.replace" do
+  before :each do
+    @orig = ENV.to_hash
+    ENV.delete("foo")
+  end
+
+  after :each do
+    ENV.replace(@orig)
+  end
 
   it "replaces ENV with a Hash" do
-    ENV["foo"] = "bar"
-    e = ENV.reject { |k, v| k == "foo" }
-    e["baz"] = "bam"
-    ENV.replace e
-    ENV["foo"].should == nil
-    ENV["baz"].should == "bam"
-    ENV.delete "baz"
+    ENV.replace("foo" => "0", "bar" => "1").should equal(ENV)
+    ENV.size.should == 2
+    ENV["foo"].should == "0"
+    ENV["bar"].should == "1"
+  end
+
+  it "raises TypeError if the argument is not a Hash" do
+    -> { ENV.replace(Object.new) }.should raise_error(TypeError, "no implicit conversion of Object into Hash")
+    ENV.to_hash.should == @orig
+  end
+
+  it "raises TypeError if a key is not a String" do
+    -> { ENV.replace(Object.new => "0") }.should raise_error(TypeError, "no implicit conversion of Object into String")
+    ENV.to_hash.should == @orig
+  end
+
+  it "raises TypeError if a value is not a String" do
+    -> { ENV.replace("foo" => Object.new) }.should raise_error(TypeError, "no implicit conversion of Object into String")
+    ENV.to_hash.should == @orig
+  end
+
+  it "raises Errno::EINVAL when the key contains the '=' character" do
+    -> { ENV.replace("foo=" =>"bar") }.should raise_error(Errno::EINVAL)
+  end
+
+  it "raises Errno::EINVAL when the key is an empty string" do
+    -> { ENV.replace("" => "bar") }.should raise_error(Errno::EINVAL)
+  end
+
+  it "does not accept good data preceding an error" do
+    -> { ENV.replace("foo" => "1", Object.new => Object.new) }.should raise_error(TypeError, "no implicit conversion of Object into String")
   end
 
+  it "does not accept good data following an error" do
+    -> { ENV.replace(Object.new => Object.new, "foo" => "0") }.should raise_error(TypeError, "no implicit conversion of Object into String")
+    ENV.to_hash.should == @orig
+  end
 end
diff --git a/spec/ruby/core/env/shared/to_hash.rb b/spec/ruby/core/env/shared/to_hash.rb
index 254054c14d..bfa5699e8d 100644
--- a/spec/ruby/core/env/shared/to_hash.rb
+++ b/spec/ruby/core/env/shared/to_hash.rb
@@ -1,10 +1,17 @@
 describe :env_to_hash, shared: true do
+  before :each do
+    @saved_foo = ENV["foo"]
+  end
+
+  after :each do
+    ENV["foo"]= @saved_foo
+  end
+
   it "returns the ENV as a hash" do
     ENV["foo"] = "bar"
     h = ENV.send(@method)
     h.should be_an_instance_of(Hash)
     h["foo"].should == "bar"
-    ENV.delete "foo"
   end
 
   it "uses the locale encoding for keys" do
@@ -18,5 +25,9 @@ describe :env_to_hash, shared: true do
   it "duplicates the ENV when converting to a Hash" do
     h = ENV.send(@method)
     h.should_not equal ENV
+    h.size.should == ENV.size
+    h.each_pair do |k, v|
+      ENV[k].should == v
+    end
   end
 end
diff --git a/spec/ruby/core/env/shared/update.rb b/spec/ruby/core/env/shared/update.rb
index 430cda5185..129a56544c 100644
--- a/spec/ruby/core/env/shared/update.rb
+++ b/spec/ruby/core/env/shared/update.rb
@@ -9,8 +9,8 @@ describe :env_update, shared: true do
     ENV["bar"] = @saved_bar
   end
 
-  it "adds the parameter hash to ENV" do
-    ENV.send @method, {"foo" => "0", "bar" => "1"}
+  it "adds the parameter hash to ENV, returning ENV" do
+    ENV.send(@method, "foo" => "0", "bar" => "1").should equal(ENV)
     ENV["foo"].should == "0"
     ENV["bar"].should == "1"
   end
@@ -19,17 +19,43 @@ describe :env_update, shared: true do
     ENV.send(@method, {"foo" => "0", "bar" => "1"}).should equal(ENV)
   end
 
-  it "yields key, the old value and the new value when replacing entries" do
+  it "yields key, the old value and the new value when replacing an entry" do
     ENV.send @method, {"foo" => "0", "bar" => "3"}
     a = []
     ENV.send @method, {"foo" => "1", "bar" => "4"} do |key, old, new|
       a << [key, old, new]
+      new
+    end
+    a[0].should == ["foo", "0", "1"]
+    a[1].should == ["bar", "3", "4"]
+  end
+
+  it "yields key, the old value and the new value when replacing an entry" do
+    ENV.send @method, {"foo" => "0", "bar" => "3"}
+    ENV.send @method, {"foo" => "1", "bar" => "4"} do |key, old, new|
       (new.to_i + 1).to_s
     end
     ENV["foo"].should == "2"
     ENV["bar"].should == "5"
-    a[0].should == ["foo", "0", "1"]
-    a[1].should == ["bar", "3", "4"]
+  end
+
+  ruby_version_is "2.7" do
+    # BUG: https://bugs.ruby-lang.org/issues/16192
+    it "does not evaluate the block when the name is new" do
+      ENV.delete("bar")
+      ENV.send @method, {"foo" => "0"}
+      ENV.send(@method, "bar" => "1") { |key, old, new| fail "Should not get here" }
+      ENV["bar"].should == "1"
+    end
+
+    # BUG: https://bugs.ruby-lang.org/issues/16192
+    it "does not use the block's return value as the value when the name is new" do
+      ENV.delete("bar")
+      ENV.send @method, {"foo" => "0"}
+      ENV.send(@method, "bar" => "1") { |key, old, new| "Should not use this value" }
+      ENV["foo"].should == "0"
+      ENV["bar"].should == "1"
+    end
   end
 
   it "returns ENV when block given" do
@@ -44,6 +70,14 @@ describe :env_update, shared: true do
     -> { ENV.send @method, "foo" => Object.new }.should raise_error(TypeError, "no implicit conversion of Object into String")
   end
 
+  it "raises Errno::EINVAL when a name contains the '=' character" do
+    -> { ENV.send(@method, "foo=" => "bar") }.should raise_error(Errno::EINVAL)
+  end
+
+  it "raises Errno::EINVAL when a name is an empty string" do
+    -> { ENV.send(@method, "" => "bar") }.should raise_error(Errno::EINVAL)
+  end
+
   it "updates good data preceding an error" do
     ENV["foo"] = "0"
     begin
diff --git a/spec/ruby/core/env/to_a_spec.rb b/spec/ruby/core/env/to_a_spec.rb
index ed290a48a5..25441eb029 100644
--- a/spec/ruby/core/env/to_a_spec.rb
+++ b/spec/ruby/core/env/to_a_spec.rb
@@ -3,11 +3,10 @@ require_relative '../../spec_helper'
 describe "ENV.to_a" do
 
   it "returns the ENV as an array" do
-    ENV["foo"] = "bar"
     a = ENV.to_a
     a.is_a?(Array).should == true
-    a.find { |e| e.first == "foo" }.should == ["foo", "bar"]
-    ENV.delete "foo"
+    a.size.should == ENV.size
+    ENV.each_pair { |k, v| a.should include([k, v])}
   end
 
   it "returns the entries in the locale encoding" do
diff --git a/spec/ruby/core/env/to_h_spec.rb b/spec/ruby/core/env/to_h_spec.rb
index 81a17700e9..822167aa2b 100644
--- a/spec/ruby/core/env/to_h_spec.rb
+++ b/spec/ruby/core/env/to_h_spec.rb
@@ -19,6 +19,11 @@ describe "ENV.to_h" do
         ENV.to_h { |k, v| [k, v.upcase] }.should == { 'a' => "B", 'c' => "D" }
       end
 
+      it "does not require the array elements to be strings" do
+        ENV.replace("a" => "b", "c" => "d")
+        ENV.to_h { |k, v| [k.to_sym, v.to_sym] }.should == { :a => :b, :c => :d }
+      end
+
       it "raises ArgumentError if block returns longer or shorter array" do
         -> do
           ENV.to_h { |k, v| [k, v.upcase, 1] }
diff --git a/spec/ruby/core/env/values_at_spec.rb b/spec/ruby/core/env/values_at_spec.rb
index 906d8b01f2..ee970e5f65 100644
--- a/spec/ruby/core/env/values_at_spec.rb
+++ b/spec/ruby/core/env/values_at_spec.rb
@@ -1,17 +1,37 @@
 require_relative '../../spec_helper'
 
 describe "ENV.values_at" do
+  before :each do
+    @saved_foo = ENV["foo"]
+    @saved_bar = ENV["bar"]
+  end
+
+  after :each do
+    ENV["foo"] = @saved_foo
+    ENV["bar"] = @saved_bar
+  end
 
-  it "returns an array of the values referenced by the parameters as keys" do
+  it "returns an array of the values corresponding to the given keys" do
     ENV["foo"] = "oof"
     ENV["bar"] = "rab"
-    ENV.values_at.should == []
     ENV.values_at("bar", "foo").should == ["rab", "oof"]
-    ENV.delete "foo"
-    ENV.delete "bar"
+  end
+
+  it "returns an empty array if no keys specified" do
+    ENV.values_at.should == []
+  end
+
+  it "returns nil for each key that is not a name" do
+    ENV["foo"] = "oof"
+    ENV["bar"] = "rab"
+    ENV.values_at("x", "bar", "y", "foo", "z").should == [nil, "rab", nil, "oof", nil]
   end
 
   it "uses the locale encoding" do
     ENV.values_at(ENV.keys.first).first.encoding.should == Encoding.find('locale')
   end
+
+  it "raises TypeError when a key is not coercible to String" do
+    -> { ENV.values_at("foo", Object.new) }.should raise_error(TypeError, "no implicit conversion of Object into String")
+  end
 end
diff --git a/spec/ruby/core/env/values_spec.rb b/spec/ruby/core/env/values_spec.rb
index 2e4e69c23b..919d7ffb7c 100644
--- a/spec/ruby/core/env/values_spec.rb
+++ b/spec/ruby/core/env/values_spec.rb
@@ -3,14 +3,7 @@ require_relative '../../spec_helper'
 describe "ENV.values" do
 
   it "returns an array of the values" do
-    orig = ENV.to_hash
-    begin
-      ENV.replace "a" => "b", "c" => "d"
-      a = ENV.values
-      a.sort.should == ["b", "d"]
-    ensure
-      ENV.replace orig
-    end
+    ENV.values.should == ENV.to_hash.values
   end
 
   it "uses the locale encoding" do