Merge pull request #2740 from ruby/slice-lines

Location#slice_lines, Node#slice_lines

lib/prism/parse_result.rb

@@ -45,6 +45,12 @@ def line_start(byte_offset)
       offsets[find_line(byte_offset)]
     end
 
+    # Returns the byte offset of the end of the line corresponding to the given
+    # byte offset.
+    def line_end(byte_offset)
+      offsets[find_line(byte_offset) + 1] || source.bytesize
+    end
+
     # Return the column number for the given byte offset.
     def column(byte_offset)
       byte_offset - line_start(byte_offset)
@@ -176,6 +182,15 @@ def slice
       source.slice(start_offset, length)
     end
 
+    # The source code that this location represents starting from the beginning
+    # of the line that this location starts on to the end of the line that this
+    # location ends on.
+    def slice_lines
+      line_start = source.line_start(start_offset)
+      line_end = source.line_end(end_offset)
+      source.slice(line_start, line_end - line_start)
+    end
+
     # The character offset from the beginning of the source where this location
     # starts.
     def start_character_offset

rbi/prism/inspect_visitor.rbi

@@ -1,10 +1,10 @@
 # typed: strict
 
 class Prism::InspectVisitor < Prism::Visitor
-  sig { params(String).void }
+  sig { params(indent: String).void }
   def initialize(indent = ""); end
 
-  sig { params(Prism::Node).returns(String) }
+  sig { params(node: Prism::Node).returns(String) }
   def self.compose(node); end
 
   sig { returns(String) }

sig/prism/parse_result.rbs

@@ -9,6 +9,7 @@ module Prism
     def slice: (Integer byte_offset, Integer length) -> String
     def line: (Integer byte_offset) -> Integer
     def line_start: (Integer byte_offset) -> Integer
+    def line_end: (Integer byte_offset) -> Integer
     def line_offset: (Integer byte_offset) -> Integer
     def column: (Integer byte_offset) -> Integer
     def character_offset: (Integer byte_offset) -> Integer
@@ -31,6 +32,7 @@ module Prism
     def copy: (?source: Source, ?start_offset: Integer, ?length: Integer) -> Location
     def chop: () -> Location
     def slice: () -> String
+    def slice_lines: () -> String
     def start_character_offset: () -> Integer
     def end_offset: () -> Integer
     def end_character_offset: () -> Integer

templates/lib/prism/node.rb.erb

@@ -45,6 +45,13 @@ module Prism
       location.slice
     end
 
+    # Slice the location of the node from the source, starting at the beginning
+    # of the line that the location starts on, ending at the end of the line
+    # that the location ends on.
+    def slice_lines
+      location.slice_lines
+    end
+
     # Similar to inspect, but respects the current level of indentation given by
     # the pretty print object.
     def pretty_print(q)

templates/rbi/prism/node.rbi.erb

@@ -16,6 +16,9 @@ class Prism::Node
   sig { returns(String) }
   def slice; end
 
+  sig { returns(String) }
+  def slice_lines; end
+
   sig { params(q: T.untyped).void }
   def pretty_print(q); end
 

templates/sig/prism/node.rbs.erb

@@ -13,6 +13,7 @@ module Prism
     def start_offset: () -> Integer
     def end_offset: () -> Integer
     def slice: () -> String
+    def slice_lines: () -> String
     def pretty_print: (untyped q) -> untyped
     def to_dot: () -> String
   end

test/prism/ruby_api_test.rb

@@ -209,6 +209,13 @@ def test_location_chop
       assert_equal "", location.slice
     end
 
+    def test_location_slice_lines
+      result = Prism.parse("\nprivate def foo\nend\n")
+      method = result.value.statements.body.first.arguments.arguments.first
+
+      assert_equal "private def foo\nend\n", method.slice_lines
+    end
+
     def test_heredoc?
       refute parse_expression("\"foo\"").heredoc?
       refute parse_expression("\"foo \#{1}\"").heredoc?