fix pry indent frozen error (#2136)

* fix pry indent frozen error

* fix generation of mutable strings

* fix String.new with no argument

* rubocop: fix offences of the Style/EmptyLiteral cop

2 files changed, 9 insertions, 1 deletions

diff --git a/lib/pry/indent.rb b/lib/pry/indent.rb
index 963758a6..2d19d87e 100644
--- a/lib/pry/indent.rb
+++ b/lib/pry/indent.rb
@@ -109,7 +109,7 @@ class Pry
     # reset internal state
     def reset
       @stack = []
-      @indent_level = ''
+      @indent_level = String.new # rubocop:disable Style/EmptyLiteral
       @heredoc_queue = []
       @close_heredocs = {}
       @string_start = nil
diff --git a/spec/indent_spec.rb b/spec/indent_spec.rb
index 29c07a5f..a705d8bc 100644
--- a/spec/indent_spec.rb
+++ b/spec/indent_spec.rb
@@ -305,6 +305,14 @@ OUTPUT
     expect(@indent.indent(input)).to eq output
   end
 
+  it "should not raise error, if MIDWAY_TOKENS are used without indentation" do
+    expect { @indent.indent("when") }.not_to raise_error
+    expect { @indent.reset.indent("else") }.not_to raise_error
+    expect { @indent.reset.indent("elsif") }.not_to raise_error
+    expect { @indent.reset.indent("ensure") }.not_to raise_error
+    expect { @indent.reset.indent("rescue") }.not_to raise_error
+  end
+
   describe "nesting" do
     test = File.read("spec/fixtures/example_nesting.rb")