Instead of accessing the struct as an array, access it via methods. There are other places inside of this file already using this API (for example e0a5c3d2b7/lib/irb/ruby-lex.rb (L829-L830)).
This commit moves all struct array-ish calls to use their method calls instead. It is also ~1.23 faster accessing values via a method instead of as an array according to this microbenchmark:
```ruby
Elem = Struct.new(:pos, :event, :tok, :state, :message) do
def initialize(pos, event, tok, state, message = nil)
super(pos, event, tok, State.new(state), message)
end
# ...
def to_a
a = super
a.pop unless a.empty?
a
end
end
class ElemClass
attr_accessor :pos, :event, :tok, :state, :message
def initialize(pos, event, tok, state, message = nil)
@pos = pos
@event = event
@tok = tok
@state = State.new(state)
@message = message
end
def to_a
if @message
[@pos, @event, @tok, @state, @message]
else
[@pos, @event, @tok, @state]
end
end
end
# stub state class creation for now
class State; def initialize(val); end; end
```
```ruby
Benchmark.ips do |x|
x.report("struct") { struct[1] }
x.report("class ") { from_class.event }
x.compare!
end; nil
```
```
Warming up --------------------------------------
struct 1.624M i/100ms
class 1.958M i/100ms
Calculating -------------------------------------
struct 17.139M (± 2.6%) i/s - 86.077M in 5.025801s
class 21.104M (± 3.4%) i/s - 105.709M in 5.015193s
Comparison:
class : 21103826.3 i/s
struct: 17139201.5 i/s - 1.23x (± 0.00) slower
```
https://github.com/ruby/irb/issues/55
If we had put multiple open braces on a line the with no closing brace
spaces_of_nest array keeps getting '0' added to it. This means that when
we pop off of this array we are saying that we should be in position zero
for the next line. This is an issue because we don't always want to be
in position 0 after a closing brace.
Example:
```
[[[
]
]
]
```
In the above example the 'spaces_of_nest' array looks like this after
the first line is entered: [0,0,0]. We really want to be indented 4
spaces for the 1st closing brace 2 for the 2nd and 0 for the 3rd. i.e.
we want it to be: [0,2,4].
We also saw this issue with a heredoc inside of an array.
```
[<<FOO]
hello
FOO
```
https://github.com/ruby/irb/commit/80c69c8272
This commit fixes the check_newline_depth_difference method to multiple
open braces on one line into account. Before this change we were
subtracting from the depth in check_newline_depth_difference on
every open brace. This is the right thing to do if the opening and
closing brace are on the same line. For example in a method definition we
have an opening and closing parentheses we want to add 1 to our depth,
and then remove it.
```
def foo()
end
```
However this isn't the correct behavior when the brace spans multiple
lines. If a brace spans multiple lines we don't want to subtract from
check_newline_depth_difference and we want to treat the braces the same
way as we do `end` and allow check_corresponding_token_depth to pop the
correct depth.
Example of bad behavior:
```
def foo()
[
]
puts 'bar'
end
```
Example of desired behavior:
```
def foo()
[
]
puts 'bar'
end
```
https://github.com/ruby/irb/commit/7dc8af01e0
The set_auto_indent method calculates the correct number of spaces for
indenting a line. We think there might be a few bugs in this method so
we are testing the current functionality to make sure nothing breaks
when we address those bugs.
Example test failure:
```
1) Failure:
TestIRB::TestRubyLex#test_auto_indent [/Users/Ben/Projects/irb/test/irb/test_ruby_lex.rb:75]:
Calculated the wrong number of spaces for:
def each_top_level_statement
initialize_input
catch(:TERM_INPUT) do
loop do
begin
prompt
unless l = lex
throw :TERM_INPUT if @line == ''
else
.
<10> expected but was
<12>.
```
https://github.com/ruby/irb/commit/752d5597ab
Kaíque Kandy Koga
schneems
aycabta
Hiroshi SHIBATA
Nobuhiro IMAI
Kazuhiro NISHIYAMA
Ben