Manually merge syntax_suggest-1.1.0

6 files changed, 199 insertions, 142 deletions

diff --git a/lib/syntax_suggest/around_block_scan.rb b/lib/syntax_suggest/around_block_scan.rb
index 346a7a99ad..ce00431b3a 100644
--- a/lib/syntax_suggest/around_block_scan.rb
+++ b/lib/syntax_suggest/around_block_scan.rb
@@ -117,133 +117,6 @@ module SyntaxSuggest
       self
     end
 
-    # Shows surrounding kw/end pairs
-    #
-    # The purpose of showing these extra pairs is due to cases
-    # of ambiguity when only one visible line is matched.
-    #
-    # For example:
-    #
-    #     1  class Dog
-    #     2    def bark
-    #     4    def eat
-    #     5    end
-    #     6  end
-    #
-    # In this case either line 2 could be missing an `end` or
-    # line 4 was an extra line added by mistake (it happens).
-    #
-    # When we detect the above problem it shows the issue
-    # as only being on line 2
-    #
-    #     2    def bark
-    #
-    # Showing "neighbor" keyword pairs gives extra context:
-    #
-    #     2    def bark
-    #     4    def eat
-    #     5    end
-    #
-    def capture_before_after_kws
-      lines = []
-      up_stop_next = false
-      down_stop_next = false
-      @scanner.commit_if_changed
-
-      lines = []
-      @scanner.scan(
-        up: ->(line, kw_count, end_count) {
-          break if up_stop_next
-          next true if line.empty?
-          break if line.indent < @orig_indent
-          next true if line.indent != @orig_indent
-
-          # If we're going up and have one complete kw/end pair, stop
-          if kw_count != 0 && kw_count == end_count
-            lines << line
-            break
-          end
-
-          lines << line if line.is_kw? || line.is_end?
-        },
-        down: ->(line, kw_count, end_count) {
-          break if down_stop_next
-          next true if line.empty?
-          break if line.indent < @orig_indent
-          next true if line.indent != @orig_indent
-
-          # if we're going down and have one complete kw/end pair,stop
-          if kw_count != 0 && kw_count == end_count
-            lines << line
-            break
-          end
-
-          lines << line if line.is_kw? || line.is_end?
-        }
-      )
-      @scanner.stash_changes
-      lines
-    end
-
-    # Shows the context around code provided by "falling" indentation
-    #
-    #
-    # If this is the original code lines:
-    #
-    #   class OH
-    #     def hello
-    #       it "foo" do
-    #     end
-    #   end
-    #
-    # And this is the line that is captured
-    #
-    #       it "foo" do
-    #
-    # It will yield its surrounding context:
-    #
-    #   class OH
-    #     def hello
-    #     end
-    #   end
-    #
-    # Example:
-    #
-    #   AroundBlockScan.new(
-    #       block: block,
-    #       code_lines: @code_lines
-    #   ).on_falling_indent do |line|
-    #     @lines_to_output << line
-    #   end
-    #
-    def on_falling_indent
-      last_indent_up = @orig_indent
-      last_indent_down = @orig_indent
-
-      @scanner.commit_if_changed
-      @scanner.scan(
-        up: ->(line, _, _) {
-          next true if line.empty?
-
-          if line.indent < last_indent_up
-            yield line
-            last_indent_up = line.indent
-          end
-          true
-        },
-        down: ->(line, _, _) {
-          next true if line.empty?
-          if line.indent < last_indent_down
-            yield line
-            last_indent_down = line.indent
-          end
-          true
-        }
-      )
-      @scanner.stash_changes
-      self
-    end
-
     # Scanning is intentionally conservative because
     # we have no way of rolling back an agressive block (at this time)
     #
@@ -275,24 +148,28 @@ module SyntaxSuggest
 
       return self if kw_count == end_count # nothing to balance
 
-      @scanner.commit_if_changed
-      scan_while { |line| line.empty? }
+      @scanner.commit_if_changed # Rollback point if we don't find anything to optimize
+
+      # Try to eat up empty lines
+      @scanner.scan(
+        up: ->(line, _, _) { line.hidden? || line.empty? },
+        down: ->(line, _, _) { line.hidden? || line.empty? }
+      )
 
       # More ends than keywords, check if we can balance expanding up
       next_up = @scanner.next_up
       next_down = @scanner.next_down
-      if (end_count - kw_count) == 1 && next_up
-        if next_up.is_kw? && next_up.indent >= @target_indent
+      case end_count - kw_count
+      when 1
+        if next_up&.is_kw? && next_up.indent >= @target_indent
           @scanner.scan(
             up: ->(line, _, _) { line == next_up },
             down: ->(line, _, _) { false }
           )
           @scanner.commit_if_changed
         end
-
-      # More keywords than ends, check if we can balance by expanding down
-      elsif (kw_count - end_count) == 1 && next_down
-        if next_down.is_end? && next_down.indent >= @target_indent
+      when -1
+        if next_down&.is_end? && next_down.indent >= @target_indent
           @scanner.scan(
             up: ->(line, _, _) { false },
             down: ->(line, _, _) { line == next_down }
@@ -300,7 +177,7 @@ module SyntaxSuggest
           @scanner.commit_if_changed
         end
       end
-
+      # Rollback any uncommitted changes
       @scanner.stash_changes
 
       self
diff --git a/lib/syntax_suggest/capture/before_after_keyword_ends.rb b/lib/syntax_suggest/capture/before_after_keyword_ends.rb
new file mode 100644
index 0000000000..f53c57a4d1
--- /dev/null
+++ b/lib/syntax_suggest/capture/before_after_keyword_ends.rb
@@ -0,0 +1,85 @@
+# frozen_string_literal: true
+
+module SyntaxSuggest
+  module Capture
+    # Shows surrounding kw/end pairs
+    #
+    # The purpose of showing these extra pairs is due to cases
+    # of ambiguity when only one visible line is matched.
+    #
+    # For example:
+    #
+    #     1  class Dog
+    #     2    def bark
+    #     4    def eat
+    #     5    end
+    #     6  end
+    #
+    # In this case either line 2 could be missing an `end` or
+    # line 4 was an extra line added by mistake (it happens).
+    #
+    # When we detect the above problem it shows the issue
+    # as only being on line 2
+    #
+    #     2    def bark
+    #
+    # Showing "neighbor" keyword pairs gives extra context:
+    #
+    #     2    def bark
+    #     4    def eat
+    #     5    end
+    #
+    #
+    # Example:
+    #
+    #   lines = BeforeAfterKeywordEnds.new(
+    #     block: block,
+    #     code_lines: code_lines
+    #   ).call()
+    #
+    class BeforeAfterKeywordEnds
+      def initialize(code_lines:, block:)
+        @scanner = ScanHistory.new(code_lines: code_lines, block: block)
+        @original_indent = block.current_indent
+      end
+
+      def call
+        lines = []
+
+        @scanner.scan(
+          up: ->(line, kw_count, end_count) {
+            next true if line.empty?
+            break if line.indent < @original_indent
+            next true if line.indent != @original_indent
+
+            # If we're going up and have one complete kw/end pair, stop
+            if kw_count != 0 && kw_count == end_count
+              lines << line
+              break
+            end
+
+            lines << line if line.is_kw? || line.is_end?
+            true
+          },
+          down: ->(line, kw_count, end_count) {
+            next true if line.empty?
+            break if line.indent < @original_indent
+            next true if line.indent != @original_indent
+
+            # if we're going down and have one complete kw/end pair,stop
+            if kw_count != 0 && kw_count == end_count
+              lines << line
+              break
+            end
+
+            lines << line if line.is_kw? || line.is_end?
+            true
+          }
+        )
+        @scanner.stash_changes
+
+        lines
+      end
+    end
+  end
+end
diff --git a/lib/syntax_suggest/capture/falling_indent_lines.rb b/lib/syntax_suggest/capture/falling_indent_lines.rb
new file mode 100644
index 0000000000..1e046b2ba5
--- /dev/null
+++ b/lib/syntax_suggest/capture/falling_indent_lines.rb
@@ -0,0 +1,71 @@
+# frozen_string_literal: true
+
+module SyntaxSuggest
+  module Capture
+    # Shows the context around code provided by "falling" indentation
+    #
+    # If this is the original code lines:
+    #
+    #   class OH
+    #     def hello
+    #       it "foo" do
+    #     end
+    #   end
+    #
+    # And this is the line that is captured
+    #
+    #       it "foo" do
+    #
+    # It will yield its surrounding context:
+    #
+    #   class OH
+    #     def hello
+    #     end
+    #   end
+    #
+    # Example:
+    #
+    #   FallingIndentLines.new(
+    #       block: block,
+    #       code_lines: @code_lines
+    #   ).call do |line|
+    #     @lines_to_output << line
+    #   end
+    #
+    class FallingIndentLines
+      def initialize(code_lines:, block:)
+        @lines = nil
+        @scanner = ScanHistory.new(code_lines: code_lines, block: block)
+        @original_indent = block.current_indent
+      end
+
+      def call(&yieldable)
+        last_indent_up = @original_indent
+        last_indent_down = @original_indent
+
+        @scanner.commit_if_changed
+        @scanner.scan(
+          up: ->(line, _, _) {
+            next true if line.empty?
+
+            if line.indent < last_indent_up
+              yieldable.call(line)
+              last_indent_up = line.indent
+            end
+            true
+          },
+          down: ->(line, _, _) {
+            next true if line.empty?
+
+            if line.indent < last_indent_down
+              yieldable.call(line)
+              last_indent_down = line.indent
+            end
+            true
+          }
+        )
+        @scanner.stash_changes
+      end
+    end
+  end
+end
diff --git a/lib/syntax_suggest/capture_code_context.rb b/lib/syntax_suggest/capture_code_context.rb
index 71f5b271b5..6dc7047176 100644
--- a/lib/syntax_suggest/capture_code_context.rb
+++ b/lib/syntax_suggest/capture_code_context.rb
@@ -1,6 +1,14 @@
 # frozen_string_literal: true
 
 module SyntaxSuggest
+  module Capture
+  end
+end
+
+require_relative "capture/falling_indent_lines"
+require_relative "capture/before_after_keyword_ends"
+
+module SyntaxSuggest
   # Turns a "invalid block(s)" into useful context
   #
   # There are three main phases in the algorithm:
@@ -81,10 +89,10 @@ module SyntaxSuggest
     #   end
     #
     def capture_falling_indent(block)
-      AroundBlockScan.new(
+      Capture::FallingIndentLines.new(
         block: block,
         code_lines: @code_lines
-      ).on_falling_indent do |line|
+      ).call do |line|
         @lines_to_output << line
       end
     end
@@ -119,8 +127,10 @@ module SyntaxSuggest
     def capture_before_after_kws(block)
       return unless block.visible_lines.count == 1
 
-      around_lines = AroundBlockScan.new(code_lines: @code_lines, block: block)
-        .capture_before_after_kws
+      around_lines = Capture::BeforeAfterKeywordEnds.new(
+        code_lines: @code_lines,
+        block: block
+      ).call
 
       around_lines -= block.lines
 
diff --git a/lib/syntax_suggest/scan_history.rb b/lib/syntax_suggest/scan_history.rb
index 2be4aaf3c0..d15597c440 100644
--- a/lib/syntax_suggest/scan_history.rb
+++ b/lib/syntax_suggest/scan_history.rb
@@ -3,8 +3,21 @@
 module SyntaxSuggest
   # Scans up/down from the given block
   #
-  # You can snapshot a change by committing it and rolling back.
+  # You can try out a change, stash it, or commit it to save for later
   #
+  # Example:
+  #
+  #   scanner = ScanHistory.new(code_lines: code_lines, block: block)
+  #   scanner.scan(
+  #     up: ->(_, _, _) { true },
+  #     down: ->(_, _, _) { true }
+  #   )
+  #   scanner.changed? # => true
+  #   expect(scanner.lines).to eq(code_lines)
+  #
+  #   scanner.stash_changes
+  #
+  #   expect(scanner.lines).to_not eq(code_lines)
   class ScanHistory
     attr_reader :before_index, :after_index
 
@@ -25,6 +38,7 @@ module SyntaxSuggest
     # Discards any changes that have not been committed
     def stash_changes
       refresh_index
+      self
     end
 
     # Discard changes that have not been committed and revert the last commit
diff --git a/lib/syntax_suggest/version.rb b/lib/syntax_suggest/version.rb
index d816cb96cf..ac8c2f62e5 100644
--- a/lib/syntax_suggest/version.rb
+++ b/lib/syntax_suggest/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module SyntaxSuggest
-  VERSION = "1.0.4"
+  VERSION = "1.1.0"
 end