Fix Linter ControlStatementSpacing raise incorrect = (#164)

This commit is to resolve issue
#101 .

I'm not familiar with OSS, so I apologize if I'm being impolite.

I'm also using machine translation for English.

lib/slim_lint/linter/control_statement_spacing.rb

@@ -9,8 +9,14 @@ class Linter::ControlStatementSpacing < Linter
 
     on [:html, :tag, anything, [],
          [:slim, :output, anything, capture(:ruby, anything)]] do |sexp|
-      # Fetch original Slim code that contains an element with a control statement.
-      line = document.source_lines[sexp.line - 1]
+      # Process original slim code so that multi-line attributes become single line.
+      # And store the correction line count
+      source = merge_multiline_attributes(document.source_lines)
+
+      # Fetch processed Slim code that contains an element with a control statement.
+      line = source[sexp.line - 1][:line]
+      # Apply correction to the line count.
+      sexp.line += source[sexp.line - 1][:line_count]
 
       # Remove any Ruby code, because our regexp below must not match inside Ruby.
       ruby = captures[:ruby]
@@ -20,5 +26,29 @@ class Linter::ControlStatementSpacing < Linter
 
       report_lint(sexp, MESSAGE)
     end
+
+    private
+
+    def merge_multiline_attributes(source_lines)
+      result = []
+      memo = ''
+      correction_line_count = 0
+
+      source_lines.each do |line|
+        memo += line.chomp('\\')
+
+        # Lines ending in a backslash are concatenated with the next line
+        # And count the number of lines to correct the sexp line count.
+        if line.match?(/\\$/)
+          correction_line_count += 1
+          next
+        end
+
+        # Add merged rows and correction line count to the result and reset the memo
+        result << { line: memo, line_count: correction_line_count }
+        memo = ''
+      end
+      result
+    end
   end
 end

spec/slim_lint/linter/control_statement_spacing_spec.rb

@@ -175,6 +175,104 @@
     it { should_not report_lint }
   end
 
+  context 'when an element has a multi-line attribute' do
+    # OK
+    context 'when it is simple' do
+      let(:slim) { <<-'SLIM' }
+        div class='one \
+          two'
+        div = some_method
+      SLIM
+
+      it { should_not report_lint }
+    end
+
+    context 'when it is more than two lines' do
+      let(:slim) { <<-'SLIM' }
+        div class='one \
+          two three four \
+          five six seven \
+          eight nine ten eleven twelve'
+        div = some_method
+      SLIM
+
+      it { should_not report_lint }
+    end
+
+    context 'when it has more than two locations' do
+      let(:slim) { <<-'SLIM' }
+        div class='one \
+          two'
+        div class='one \
+          two three four five six seven \
+          eight nine ten eleven twelve'
+        div class='one \
+          two three four five six seven \
+          eight nine ten eleven twelve'
+        div = some_method
+      SLIM
+
+      it { should_not report_lint }
+    end
+
+    # NG
+    context 'when it is simple' do
+      let(:slim) { <<-'SLIM' }
+        div class='one \
+          two'
+        div= some_method
+      SLIM
+
+      it { should report_lint line: 3 }
+    end
+
+    context 'when it is more than two lines' do
+      let(:slim) { <<-'SLIM' }
+        div class='one \
+          two three four \
+          five six seven \
+          eight nine ten eleven twelve'
+        div =some_method
+      SLIM
+
+      it { should report_lint line: 5 }
+    end
+
+    context 'when it has more than two locations' do
+      let(:slim) { <<-'SLIM' }
+        div class='one \
+          two'
+        div class='one \
+          two three four five six seven \
+          eight nine ten eleven twelve'
+        div class='one \
+          two three four five six seven \
+          eight nine ten eleven twelve'
+        div=some_method
+      SLIM
+
+      it { should report_lint line: 9 }
+    end
+
+    context 'when it has more than two locations and verify the correctness of the line count.' do
+      let(:slim) { <<-'SLIM' }
+        div class='one \
+          two'
+        div class='one \
+          two three four five six seven \
+          eight nine ten eleven twelve'
+        div=some_method_one
+        div class='one \
+          two three four five six seven \
+          eight nine ten eleven twelve'
+        div=some_method_two
+      SLIM
+
+      it { should report_lint line: 6 }
+      it { should report_lint line: 10 }
+    end
+  end
+
   context 'when leading whitespace (=<) is used' do
     context 'and it has appropriate spacing' do
       let(:slim) { 'title =< "Something"' }