shard-ameba/spec/ameba/rule/performance/first_last_after_filter_spec.cr

99 lines
3.1 KiB
Crystal

require "../../../spec_helper"
module Ameba::Rule::Performance
subject = FirstLastAfterFilter.new
describe FirstLastAfterFilter do
it "passes if there is no potential performance improvements" do
expect_no_issues subject, <<-CRYSTAL
[1, 2, 3].select { |e| e > 1 }
[1, 2, 3].reverse.select { |e| e > 1 }
[1, 2, 3].reverse.last
[1, 2, 3].reverse.first
[1, 2, 3].reverse.first
CRYSTAL
end
it "reports if there is select followed by last" do
expect_issue subject, <<-CRYSTAL
[1, 2, 3].select { |e| e > 2 }.last
# ^^^^^^^^^^^^^^^^^^^^^^^^^^ error: Use `reverse_each.find {...}` instead of `select {...}.last`
CRYSTAL
end
it "does not report if source is a spec" do
expect_no_issues subject, path: "source_spec.cr", code: <<-CRYSTAL
[1, 2, 3].select { |e| e > 2 }.last
CRYSTAL
end
it "reports if there is select followed by last?" do
expect_issue subject, <<-CRYSTAL
[1, 2, 3].select { |e| e > 2 }.last?
# ^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: Use `reverse_each.find {...}` instead of `select {...}.last?`
CRYSTAL
end
it "reports if there is select followed by first" do
expect_issue subject, <<-CRYSTAL
[1, 2, 3].select { |e| e > 2 }.first
# ^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: Use `find {...}` instead of `select {...}.first`
CRYSTAL
end
it "does not report if there is selected followed by first with arguments" do
expect_no_issues subject, <<-CRYSTAL
[1, 2, 3].select { |n| n % 2 == 0 }.first(2)
CRYSTAL
end
it "reports if there is select followed by first?" do
expect_issue subject, <<-CRYSTAL
[1, 2, 3].select { |e| e > 2 }.first?
# ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: Use `find {...}` instead of `select {...}.first?`
CRYSTAL
end
it "does not report if there is select followed by any other call" do
expect_no_issues subject, <<-CRYSTAL
[1, 2, 3].select { |e| e > 2 }.size
[1, 2, 3].select { |e| e > 2 }.any?
CRYSTAL
end
context "properties" do
it "allows to configure object_call_names" do
rule = Rule::Performance::FirstLastAfterFilter.new
rule.filter_names = %w(reject)
expect_no_issues rule, <<-CRYSTAL
[1, 2, 3].select { |e| e > 2 }.first
CRYSTAL
end
end
it "reports rule, pos and message" do
s = Source.new %(
[1, 2, 3].select { |e| e > 2 }.first
), "source.cr"
subject.catch(s).should_not be_valid
s.issues.size.should eq 1
issue = s.issues.first
issue.rule.should_not be_nil
issue.location.to_s.should eq "source.cr:1:11"
issue.end_location.to_s.should eq "source.cr:1:37"
issue.message.should eq "Use `find {...}` instead of `select {...}.first`"
end
context "macro" do
it "doesn't report in macro scope" do
expect_no_issues subject, <<-CRYSTAL
{{ [1, 2, 3].select { |e| e > 2 }.last }}
CRYSTAL
end
end
end
end