Add # typeprof:ignore comment to suppress diagnostics

Append `# typeprof:ignore` at the end of a line to suppress any
diagnostic whose code range starts on that line. This is useful for
code patterns that TypeProf cannot analyze precisely.

    def check
      Foo.new.accept_int("str") # typeprof:ignore
    end

The keyword matches Steep's `# steep:ignore` to keep the Ruby type
checker ecosystem consistent.

The structure (collecting comment line ranges and filtering at
ProgramNode#each_diagnostic) is borrowed from #306 which proposed
a similar feature with `# typeprof:disable`/`enable`.

Co-Authored-By: Masato Sugiyama <public@smasato.net>
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: 3 people

lib/typeprof/core/ast.rb

@@ -16,7 +16,21 @@ def self.parse_rb(path, src)
       cref = CRef::Toplevel
       lenv = LocalEnv.new(file_context, cref, {}, [])
 
-      ProgramNode.new(raw_scope, lenv)
+      ignore_ranges = collect_ignore_ranges(result)
+      ProgramNode.new(raw_scope, lenv, ignore_ranges: ignore_ranges)
+    end
+
+    # Collect line ranges marked with `# typeprof:ignore` comments.
+    # Each range is suppressed in ProgramNode#each_diagnostic.
+    IGNORE_RE = /\A#\s*typeprof:ignore\s*\z/
+    def self.collect_ignore_ranges(prism_result)
+      ranges = []
+      prism_result.comments.each do |c|
+        next unless c.location.slice.match?(IGNORE_RE)
+        line = c.location.start_line
+        ranges << (line..line)
+      end
+      ranges
     end
 
     #: (untyped, TypeProf::Core::LocalEnv, ?bool, ?bool) -> TypeProf::Core::AST::Node

lib/typeprof/core/ast/base.rb

@@ -211,20 +211,30 @@ def pretty_print_instance_variables
     end
 
     class ProgramNode < Node
-      def initialize(raw_node, lenv)
+      def initialize(raw_node, lenv, ignore_ranges: [])
         super(raw_node, lenv)
 
         @tbl = raw_node.locals
+        @ignore_ranges = ignore_ranges
         raw_body = raw_node.statements
 
         @body = AST.create_node(raw_body, lenv, false)
       end
 
-      attr_reader :tbl, :body
+      attr_reader :tbl, :ignore_ranges, :body
 
       def subnodes = { body: }
       def attrs = { tbl: }
 
+      def each_diagnostic(genv, &blk)
+        return super if @ignore_ranges.empty?
+        super(genv) do |diag|
+          line = diag.code_range&.first&.lineno
+          next if line && @ignore_ranges.any? { |r| r.cover?(line) }
+          blk.call(diag)
+        end
+      end
+
       def install0(genv)
         @tbl.each {|var| @lenv.locals[var] = Source.new(genv.nil_type) }
         @lenv.locals[:"*self"] = lenv.cref.get_self(genv)

test/cli_test.rb

@@ -47,6 +47,17 @@ def check: -> :ok
       END
     end
 
+    def test_e2e_ignore_directive
+      assert_equal(<<~END, test_run("ignore_directive", ["--show-error", "."]))
+        # TypeProf #{ TypeProf::VERSION }
+
+        # ./ignore_directive.rb
+        class Object
+          def check: -> :ok
+        end
+      END
+    end
+
     def test_e2e_syntax_error
       assert_equal(<<~END, test_run("syntax_error", ["."]))
         # TypeProf #{ TypeProf::VERSION }

test/fixtures/ignore_directive/ignore_directive.rb

@@ -0,0 +1,3 @@
+def check
+  Foo.new.accept_int("str") # typeprof:ignore
+end

test/fixtures/ignore_directive/ignore_directive.rbs

@@ -0,0 +1,3 @@
+class Foo
+  def accept_int: (Integer) -> :ok
+end

test/lsp/lsp_test.rb

@@ -187,6 +187,51 @@ def foo(nnn)
       end
     end
 
+    def test_diagnostics_ignore_directive
+      init("basic")
+
+      notify(
+        "textDocument/didOpen",
+        textDocument: { uri: @folder + "basic.rb", version: 0, text: <<-END },
+def foo(nnn)
+  nnn
+end
+
+foo(1, 2)
+foo(1, 2) # typeprof:ignore
+foo(1, 2)
+        END
+      )
+
+      expect_notification("typeprof.enableToggleButton") {|json| }
+      expect_request("workspace/codeLens/refresh") {|json| }
+      expect_notification("textDocument/publishDiagnostics") do |json|
+        assert_equal({
+          uri: @folder + "basic.rb",
+          diagnostics: [
+            {
+              message: "wrong number of arguments (2 for 1)",
+              range: {
+                start: { line: 4, character: 0 },
+                end: { line: 4, character: 3 },
+              },
+              severity: 1,
+              source: "TypeProf",
+            },
+            {
+              message: "wrong number of arguments (2 for 1)",
+              range: {
+                start: { line: 6, character: 0 },
+                end: { line: 6, character: 3 },
+              },
+              severity: 1,
+              source: "TypeProf",
+            }
+          ],
+        }, json)
+      end
+    end
+
     def test_diagnostics2
       init("basic")