diff --git a/proc.c b/proc.c
index dfc7501252..ec08f8ad52 100644
--- a/proc.c
+++ b/proc.c
@@ -43,12 +43,202 @@ VALUE rb_cUnboundMethod;
 VALUE rb_cMethod;
 VALUE rb_cBinding;
 VALUE rb_cProc;
+static VALUE rb_cSourceRange;
 
 static rb_block_call_func bmcall;
 static int method_arity(VALUE);
 static int method_min_max_arity(VALUE, int *max);
 static VALUE proc_binding(VALUE self);
 
+struct source_range_data {
+    VALUE path;
+    VALUE absolute_path;
+    int start_line;
+    int start_column;
+    int end_line;
+    int end_column;
+};
+
+static size_t
+source_range_memsize(const void *ptr)
+{
+    return sizeof(struct source_range_data);
+}
+
+RUBY_REFERENCES(source_range_refs) = {
+    RUBY_REF_EDGE(struct source_range_data, path),
+    RUBY_REF_EDGE(struct source_range_data, absolute_path),
+    RUBY_REF_END
+};
+
+static const rb_data_type_t source_range_data_type = {
+    "source_range",
+    {
+        RUBY_REFS_LIST_PTR(source_range_refs),
+        RUBY_TYPED_DEFAULT_FREE,
+        source_range_memsize,
+    },
+    0, 0, RUBY_TYPED_FREE_IMMEDIATELY | RUBY_TYPED_WB_PROTECTED | RUBY_TYPED_DECL_MARKING
+};
+
+static VALUE
+source_range_new(const rb_iseq_t *iseq)
+{
+    if (!iseq) {
+        return Qnil;
+    }
+    rb_iseq_check(iseq);
+
+    VALUE path = rb_iseq_path(iseq);
+    VALUE absolute_path = rb_iseq_realpath(iseq);
+    if (NIL_P(path) && NIL_P(absolute_path)) {
+        return Qnil;
+    }
+
+    int start_line, start_column, end_line, end_column;
+    rb_iseq_code_location(iseq, &start_line, &start_column, &end_line, &end_column);
+
+    struct source_range_data *data;
+    VALUE obj = TypedData_Make_Struct(rb_cSourceRange, struct source_range_data, &source_range_data_type, data);
+    RB_OBJ_WRITE(obj, &data->path, path);
+    RB_OBJ_WRITE(obj, &data->absolute_path, absolute_path);
+    data->start_line = start_line;
+    data->start_column = start_column;
+    data->end_line = end_line;
+    data->end_column = end_column;
+
+    return obj;
+}
+
+static struct source_range_data *
+source_range_data_get(VALUE self)
+{
+    struct source_range_data *data;
+    TypedData_Get_Struct(self, struct source_range_data, &source_range_data_type, data);
+    return data;
+}
+
+/*
+ * call-seq:
+ *    source_range.path  -> String
+ *
+ * Returns the source path for the callable associated with this source range.
+ * This is the same path returned as the first element of #source_location.
+ */
+static VALUE
+source_range_path(VALUE self)
+{
+    return source_range_data_get(self)->path;
+}
+
+/*
+ * call-seq:
+ *    source_range.absolute_path  -> String or nil
+ *
+ * Returns the absolute source path for the callable associated with this source
+ * range, or +nil+ if the source has no absolute path, such as eval'd code.
+ */
+static VALUE
+source_range_absolute_path(VALUE self)
+{
+    return source_range_data_get(self)->absolute_path;
+}
+
+/*
+ * call-seq:
+ *    source_range.start_line  -> Integer
+ *
+ * Returns the 1-indexed line number where this source range starts.
+ */
+static VALUE
+source_range_start_line(VALUE self)
+{
+    return INT2NUM(source_range_data_get(self)->start_line);
+}
+
+/*
+ * call-seq:
+ *    source_range.start_column  -> Integer
+ *
+ * Returns the 0-indexed byte column where this source range starts.
+ *
+ *   -> {}.source_range.start_column     # => 0 # the '->'
+ *   l = -> {}.source_range.start_column # => 4 # the '->'
+ *   proc {}.source_range.start_column   # => 5 # the '{'
+ *   method(def m = 42).source_range.start_column # => 7 # the 'def'
+ */
+static VALUE
+source_range_start_column(VALUE self)
+{
+    return INT2NUM(source_range_data_get(self)->start_column);
+}
+
+/*
+ * call-seq:
+ *    source_range.end_line  -> Integer
+ *
+ * Returns the 1-indexed line number where this source range ends.
+ *
+ * Note that this does not include a potential heredoc that spans beyond the callable's end, for example:
+ *
+ *   proc { <<~HEREDOC }.source_range.end_line # => 1
+ *     heredoc
+ *     contents
+ *   HEREDOC
+ *
+ * To get the location of the final HEREDOC you can use +Prism.find(Proc|Method|UnboundMethod)+ and then compute the maximum end_line and end_column.
+ */
+static VALUE
+source_range_end_line(VALUE self)
+{
+    return INT2NUM(source_range_data_get(self)->end_line);
+}
+
+/*
+ * call-seq:
+ *    source_range.end_column  -> Integer
+ *
+ * Returns the 0-indexed byte column where this source range ends.
+ *
+ * Note that this does not include a potential heredoc that spans beyond the callable's end, for example:
+ *
+ *   proc { <<~HEREDOC }.source_range.end_column # => 19
+ *     heredoc
+ *     contents
+ *   HEREDOC
+ *
+ * To get the location of the final HEREDOC you can use +Prism.find(Proc|Method|UnboundMethod)+ and then compute the maximum end_line and end_column.
+ */
+static VALUE
+source_range_end_column(VALUE self)
+{
+    return INT2NUM(source_range_data_get(self)->end_column);
+}
+
+/*
+ * call-seq:
+ *    source_range.inspect  -> String
+ *
+ * Returns a human-readable string with the #absolute_path if available,
+ * otherwise the #path, and the start and end coordinates.
+ */
+static VALUE
+source_range_inspect(VALUE self)
+{
+    struct source_range_data *data = source_range_data_get(self);
+    VALUE str = rb_str_new_cstr("#<Ruby::SourceRange ");
+    VALUE path = NIL_P(data->absolute_path) ? data->path : data->absolute_path;
+
+    VM_ASSERT(!NIL_P(path));
+    rb_str_append(str, path);
+
+    rb_str_catf(str, ":(%d,%d)-(%d,%d)>",
+                data->start_line, data->start_column,
+                data->end_line, data->end_column);
+
+    return str;
+}
+
 /* Proc */
 
 #define IS_METHOD_PROC_IFUNC(ifunc) ((ifunc)->func == bmcall)
@@ -1562,6 +1752,25 @@ rb_proc_location(VALUE self)
     return iseq_location(rb_proc_get_iseq(self, 0));
 }
 
+/*
+ * call-seq:
+ *    prc.source_range  -> Ruby::SourceRange or nil
+ *
+ * Returns a Ruby::SourceRange for this proc, or +nil+ if this proc was
+ * not defined in Ruby (i.e. native) or has no source path.
+ *
+ * The returned Ruby::SourceRange includes the source path, absolute path when
+ * available, and the start and end line and byte-column coordinates.
+ *
+ * See https://github.com/ruby/spec/blob/master/core/proc/source_range_spec.rb
+ * for the location of start/end line/column in various cases.
+ */
+static VALUE
+rb_proc_source_range(VALUE self)
+{
+    return source_range_new(rb_proc_get_iseq(self, 0));
+}
+
 VALUE
 rb_unnamed_parameters(int arity)
 {
@@ -3231,6 +3440,31 @@ rb_method_location(VALUE method)
     return method_def_location(rb_method_def(method));
 }
 
+static VALUE
+method_def_source_range(const rb_method_definition_t *def)
+{
+    return source_range_new(method_def_iseq(def));
+}
+
+/*
+ * call-seq:
+ *    meth.source_range  -> Ruby::SourceRange or nil
+ *
+ * Returns a Ruby::SourceRange for this method, or +nil+ if this method
+ * was not defined in Ruby (i.e. native) or has no source path.
+ *
+ * The returned Ruby::SourceRange includes the source path, absolute path when
+ * available, and the start and end line and byte-column coordinates.
+ *
+ * See https://github.com/ruby/spec/blob/master/core/method/shared/source_range.rb
+ * for the location of start/end line/column in various cases.
+ */
+static VALUE
+rb_method_source_range(VALUE method)
+{
+    return method_def_source_range(rb_method_def(method));
+}
+
 static const rb_method_definition_t *
 vm_proc_method_def(VALUE procval)
 {
@@ -4278,6 +4512,28 @@ proc_ruby2_keywords(VALUE procval)
  *    SystemStackError: stack level too deep
  */
 
+/*
+ *  Document-class: Ruby::SourceRange
+ *
+ *  An object representing the source-code range for a Ruby callable.
+ *
+ *  Source ranges are returned by Proc#source_range, Method#source_range, and
+ *  UnboundMethod#source_range. They include the source path, absolute path when
+ *  available, start line, start byte column, end line, and end byte column.
+ *
+ *  The primary purpose of this class is to implement `Prism.find` precisely and cleanly on all Ruby implementations,
+ *  in a way which does not depend on implementation details like `node_id`.
+ *  For that we need the start/end line/column and the absolute_path, which is exactly what this class provides.
+ *
+ *  The user of `Prism.find` can then tweak the result as desired to, for example,
+ *  include heredocs as mentioned in Ruby::SourceRange#end_line.
+ *  Or for Proc#source_range to include the method to which the block is passed.
+ *
+ *  Note that the returned source range is not always an evaluable fragment by itself,
+ *  notably because heredocs can go beyond the `end` of the method and
+ *  for blocks because the range starts at `{`/`do`.
+ */
+
 /*
  *  Document-class: Proc
  *
@@ -4645,6 +4901,20 @@ void
 Init_Proc(void)
 {
 #undef rb_intern
+    VALUE mRuby = rb_define_module("Ruby");
+
+    /* Ruby::SourceRange */
+    rb_cSourceRange = rb_define_class_under(mRuby, "SourceRange", rb_cObject);
+    rb_undef_alloc_func(rb_cSourceRange);
+    rb_undef_method(CLASS_OF(rb_cSourceRange), "new");
+    rb_define_method(rb_cSourceRange, "path", source_range_path, 0);
+    rb_define_method(rb_cSourceRange, "absolute_path", source_range_absolute_path, 0);
+    rb_define_method(rb_cSourceRange, "start_line", source_range_start_line, 0);
+    rb_define_method(rb_cSourceRange, "start_column", source_range_start_column, 0);
+    rb_define_method(rb_cSourceRange, "end_line", source_range_end_line, 0);
+    rb_define_method(rb_cSourceRange, "end_column", source_range_end_column, 0);
+    rb_define_method(rb_cSourceRange, "inspect", source_range_inspect, 0);
+
     /* Proc */
     rb_cProc = rb_define_class("Proc", rb_cObject);
     rb_undef_alloc_func(rb_cProc);
@@ -4677,6 +4947,7 @@ Init_Proc(void)
     rb_define_method(rb_cProc, "==", proc_eq, 1);
     rb_define_method(rb_cProc, "eql?", proc_eq, 1);
     rb_define_method(rb_cProc, "source_location", rb_proc_location, 0);
+    rb_define_method(rb_cProc, "source_range", rb_proc_source_range, 0);
     rb_define_method(rb_cProc, "parameters", rb_proc_parameters, -1);
     rb_define_method(rb_cProc, "ruby2_keywords", proc_ruby2_keywords, 0);
     // rb_define_method(rb_cProc, "isolate", rb_proc_isolate, 0); is not accepted.
@@ -4718,6 +4989,7 @@ Init_Proc(void)
     rb_define_method(rb_cMethod, "owner", method_owner, 0);
     rb_define_method(rb_cMethod, "unbind", method_unbind, 0);
     rb_define_method(rb_cMethod, "source_location", rb_method_location, 0);
+    rb_define_method(rb_cMethod, "source_range", rb_method_source_range, 0);
     rb_define_method(rb_cMethod, "parameters", rb_method_parameters, 0);
     rb_define_method(rb_cMethod, "super_method", method_super_method, 0);
     rb_define_method(rb_mKernel, "method", rb_obj_method, 1);
@@ -4744,6 +5016,7 @@ Init_Proc(void)
     rb_define_method(rb_cUnboundMethod, "bind", umethod_bind, 1);
     rb_define_method(rb_cUnboundMethod, "bind_call", umethod_bind_call, -1);
     rb_define_method(rb_cUnboundMethod, "source_location", rb_method_location, 0);
+    rb_define_method(rb_cUnboundMethod, "source_range", rb_method_source_range, 0);
     rb_define_method(rb_cUnboundMethod, "parameters", rb_method_parameters, 0);
     rb_define_method(rb_cUnboundMethod, "super_method", method_super_method, 0);
 
diff --git a/spec/ruby/core/method/fixtures/classes.rb b/spec/ruby/core/method/fixtures/classes.rb
index 41904df1d1..9e180abb09 100644
--- a/spec/ruby/core/method/fixtures/classes.rb
+++ b/spec/ruby/core/method/fixtures/classes.rb
@@ -1,19 +1,20 @@
 module MethodSpecs
-
-
   class SourceLocation
-    def self.location # This needs to be on this line
-      :location       # for the spec to pass
+    LOCATION_LINE = __LINE__ + 1
+    def self.location
+      :location
     end
 
     def self.redefined
       :first
     end
 
+    REDEFINED_LINE = __LINE__ + 1
     def self.redefined
       :last
     end
 
+    ORIGINAL_LINE = __LINE__ + 1
     def original
     end
 
diff --git a/spec/ruby/core/method/shared/source_range.rb b/spec/ruby/core/method/shared/source_range.rb
new file mode 100644
index 0000000000..70884484e0
--- /dev/null
+++ b/spec/ruby/core/method/shared/source_range.rb
@@ -0,0 +1,133 @@
+require_relative '../../proc/fixtures/source_range_helpers'
+
+describe :method_source_range, shared: true do
+  it "sets absolute_path to the real path of the source file" do
+    def location
+    end
+    method = @object.call(method(:location))
+    method.source_range.absolute_path.should == File.realpath(__FILE__)
+  end
+
+  it "sets path to the source location path" do
+    def location
+    end
+    method = @object.call(method(:location))
+    method.source_range.path.should == __FILE__
+  end
+
+  it "works for singleton methods" do
+    check_source_range <<-RUBY
+    $def self.location
+      :location
+    end$
+
+    method(:location)
+    RUBY
+  end
+
+  it "works for multi-line methods" do
+    check_source_range <<-RUBY
+    $def multiline
+      1
+      2
+    end$
+
+    method(:multiline)
+    RUBY
+  end
+
+  it "works for UTF-8 method names and returns byte columns" do
+    check_source_range <<-RUBY
+    klass = Class.new do
+      $def été; 42; end$
+    end
+
+    klass.new.method(:été)
+    RUBY
+  end
+
+  it "works for inline methods" do
+    check_source_range <<-RUBY
+    klass = Class.new do
+      $def inline = 42$
+    end
+
+    klass.new.method(:inline)
+    RUBY
+  end
+
+  it "does not cover a heredoc spanning beyond an inline method" do
+    check_source_range <<-RUBY
+    $def inline_heredoc = <<~HEREDOC$
+      heredoc
+    HEREDOC
+
+    method(:inline_heredoc)
+    RUBY
+  end
+
+  it "does not cover a heredoc spanning beyond a regular method" do
+    check_source_range <<-RUBY
+    $def heredoc; <<~HEREDOC; end$;
+      heredoc
+    HEREDOC
+
+    method(:heredoc)
+    RUBY
+  end
+
+  it "works for methods defined with define_method" do
+    check_source_range <<-RUBY
+    klass = Class.new do
+      define_method(:define_method_method) ${ 42 }$
+    end
+
+    klass.new.method(:define_method_method)
+    RUBY
+  end
+
+  it "returns the same range for an unbound method as the method reports" do
+    def my_method_source_range
+      true
+    end
+
+    method = method(:my_method_source_range)
+    unbound = method.unbind
+
+    source_range_values(unbound.source_range).should == source_range_values(method.source_range)
+    unbound.source_range.path.should == method.source_range.path
+    unbound.source_range.absolute_path.should == method.source_range.absolute_path
+  end
+
+  it "returns nil for core methods" do
+    method = @object.call("".method(:length))
+
+    method.source_range.should == nil
+  end
+
+  it "sets path when absolute_path is nil" do
+    eval('def m; end', nil, "foo")
+    method = @object.call(method(:m))
+    range = method.source_range
+
+    range.path.should == "foo"
+    range.absolute_path.should == nil
+  end
+
+  it "sets #absolute_path to nil even if an absolute path is given to eval" do
+    eval('def m; end', nil, "/foo")
+    method = @object.call(method(:m))
+    range = method.source_range
+
+    range.path.should == "/foo"
+    range.absolute_path.should == nil
+  end
+
+  it "considers eval's start line" do
+    eval('def m; end', nil, "foo", 100)
+    method = @object.call(method(:m))
+    range = method.source_range
+
+    range.start_line.should == 100
+  end
+end
diff --git a/spec/ruby/core/method/source_location_spec.rb b/spec/ruby/core/method/source_location_spec.rb
index 22fcb98c74..6ab3af9f42 100644
--- a/spec/ruby/core/method/source_location_spec.rb
+++ b/spec/ruby/core/method/source_location_spec.rb
@@ -19,15 +19,15 @@ describe "Method#source_location" do
   it "sets the last value to an Integer representing the line on which the method was defined" do
     line = @method.source_location.last
     line.should.instance_of?(Integer)
-    line.should == 5
+    line.should == MethodSpecs::SourceLocation::LOCATION_LINE
   end
 
   it "returns the last place the method was defined" do
-    MethodSpecs::SourceLocation.method(:redefined).source_location.last.should == 13
+    MethodSpecs::SourceLocation.method(:redefined).source_location.last.should == MethodSpecs::SourceLocation::REDEFINED_LINE
   end
 
   it "returns the location of the original method even if it was aliased" do
-    MethodSpecs::SourceLocation.new.method(:aka).source_location.last.should == 17
+    MethodSpecs::SourceLocation.new.method(:aka).source_location.last.should == MethodSpecs::SourceLocation::ORIGINAL_LINE
   end
 
   it "works for methods defined with a block" do
diff --git a/spec/ruby/core/method/source_range_spec.rb b/spec/ruby/core/method/source_range_spec.rb
new file mode 100644
index 0000000000..46a1c6601c
--- /dev/null
+++ b/spec/ruby/core/method/source_range_spec.rb
@@ -0,0 +1,12 @@
+require_relative '../../spec_helper'
+require_relative 'shared/source_range'
+
+ruby_version_is "4.1" do
+  describe "Method#source_range" do
+    before :each do
+      @object = -> method { method }
+    end
+
+    it_behaves_like :method_source_range, :source_range
+  end
+end
diff --git a/spec/ruby/core/proc/fixtures/source_location.rb b/spec/ruby/core/proc/fixtures/source_location.rb
index 5572094630..e7a1bf5a17 100644
--- a/spec/ruby/core/proc/fixtures/source_location.rb
+++ b/spec/ruby/core/proc/fixtures/source_location.rb
@@ -1,21 +1,50 @@
 module ProcSpecs
   class SourceLocation
+    MY_PROC_LINE = __LINE__ + 2
     def self.my_proc
       proc { true }
     end
 
+    MY_LAMBDA_LINE = __LINE__ + 2
     def self.my_lambda
       -> { true }
     end
 
+    def self.my_block_lambda
+      lambda { 42 }
+    end
+
+    MY_PROC_NEW_LINE = __LINE__ + 2
     def self.my_proc_new
       Proc.new { true }
     end
 
+    MY_METHOD_LINE = __LINE__ + 1
     def self.my_method
       method(__method__).to_proc
     end
 
+    def self.my_returned_block
+      return_block { 42 }
+    end
+
+    def self.return_block(&block)
+      block
+    end
+
+    def self.my_receiver_block
+      block_receiver.foo { 42 }
+    end
+
+    def self.block_receiver
+      obj = Object.new
+      def obj.foo(&block)
+        block
+      end
+      obj
+    end
+
+    MY_MULTILINE_PROC_LINE = __LINE__ + 2
     def self.my_multiline_proc
       proc do
         'a'.upcase
@@ -23,6 +52,13 @@ module ProcSpecs
       end
     end
 
+    def self.my_heredoc_proc
+      proc { <<~END }
+        heredoc
+      END
+    end
+
+    MY_MULTILINE_LAMBDA_LINE = __LINE__ + 2
     def self.my_multiline_lambda
       -> do
         'a'.upcase
@@ -30,6 +66,7 @@ module ProcSpecs
       end
     end
 
+    MY_MULTILINE_PROC_NEW_LINE = __LINE__ + 2
     def self.my_multiline_proc_new
       Proc.new do
         'a'.upcase
@@ -37,19 +74,36 @@ module ProcSpecs
       end
     end
 
+    MY_DETACHED_PROC_LINE = __LINE__ + 2
     def self.my_detached_proc
       body = proc { true }
       proc(&body)
     end
 
+    MY_DETACHED_LAMBDA_LINE = __LINE__ + 2
     def self.my_detached_lambda
       body = -> { true }
       suppress_warning {lambda(&body)}
     end
 
+    MY_DETACHED_PROC_NEW_LINE = __LINE__ + 2
     def self.my_detached_proc_new
       body = Proc.new { true }
       Proc.new(&body)
     end
+
+    iter = Object.new
+    def iter.each(&block)
+      block.call(block)
+    end
+
+    for pr in iter
+      42
+    end
+    MY_FOR_BODY_PROC = pr
+
+    def self.my_for_body_proc
+      MY_FOR_BODY_PROC
+    end
   end
 end
diff --git a/spec/ruby/core/proc/fixtures/source_range_helpers.rb b/spec/ruby/core/proc/fixtures/source_range_helpers.rb
new file mode 100644
index 0000000000..d5a12d28ee
--- /dev/null
+++ b/spec/ruby/core/proc/fixtures/source_range_helpers.rb
@@ -0,0 +1,31 @@
+def source_range_values(range)
+  [range.start_line, range.start_column, range.end_line, range.end_column]
+end
+
+# Use <<-RUBY and not <<~RUBY to keep some spaces in front to make it more representative of a Proc in some file
+def check_source_range(source)
+  raise "Expected 2 '$' to mark start and end of source_range" unless source.count('$') == 2
+  from = source.byteindex('$')
+  to = source.byteindex('$', from+1)
+  lines = source.lines
+  from_line = 1 + source.byteslice(0, from).count("\n")
+  from_column = lines[from_line-1].byteindex('$')
+  to_line = 1 + source.byteslice(0, to).count("\n")
+  if from_line == to_line
+    to_column = lines[to_line-1].byteindex('$', from_column + 1) - 1
+  else
+    to_column = lines[to_line-1].byteindex('$')
+  end
+
+  eval_source = source.gsub('$', '')
+  result = eval(eval_source)
+  source_range = result.source_range
+  source_range.should.instance_of?(Ruby::SourceRange)
+  source_range.start_line.should == from_line
+  source_range.start_column.should == from_column
+  source_range.end_line.should == to_line
+  source_range.end_column.should == to_column
+
+  # Check consistency with source_location start line
+  result.source_location[1].should == from_line
+end
diff --git a/spec/ruby/core/proc/source_location_spec.rb b/spec/ruby/core/proc/source_location_spec.rb
index d27ad0559e..5394bed050 100644
--- a/spec/ruby/core/proc/source_location_spec.rb
+++ b/spec/ruby/core/proc/source_location_spec.rb
@@ -37,19 +37,19 @@ describe "Proc#source_location" do
   it "sets the last value to an Integer representing the line on which the proc was defined" do
     line = @proc.source_location.last
     line.should.instance_of?(Integer)
-    line.should == 4
+    line.should == ProcSpecs::SourceLocation::MY_PROC_LINE
 
     line = @proc_new.source_location.last
     line.should.instance_of?(Integer)
-    line.should == 12
+    line.should == ProcSpecs::SourceLocation::MY_PROC_NEW_LINE
 
     line = @lambda.source_location.last
     line.should.instance_of?(Integer)
-    line.should == 8
+    line.should == ProcSpecs::SourceLocation::MY_LAMBDA_LINE
 
     line = @method.source_location.last
     line.should.instance_of?(Integer)
-    line.should == 15
+    line.should == ProcSpecs::SourceLocation::MY_METHOD_LINE
   end
 
   it "works even if the proc was created on the same line" do
@@ -59,15 +59,15 @@ describe "Proc#source_location" do
   end
 
   it "returns the first line of a multi-line proc (i.e. the line containing 'proc do')" do
-    ProcSpecs::SourceLocation.my_multiline_proc.source_location.last.should == 20
-    ProcSpecs::SourceLocation.my_multiline_proc_new.source_location.last.should == 34
-    ProcSpecs::SourceLocation.my_multiline_lambda.source_location.last.should == 27
+    ProcSpecs::SourceLocation.my_multiline_proc.source_location.last.should == ProcSpecs::SourceLocation::MY_MULTILINE_PROC_LINE
+    ProcSpecs::SourceLocation.my_multiline_proc_new.source_location.last.should == ProcSpecs::SourceLocation::MY_MULTILINE_PROC_NEW_LINE
+    ProcSpecs::SourceLocation.my_multiline_lambda.source_location.last.should == ProcSpecs::SourceLocation::MY_MULTILINE_LAMBDA_LINE
   end
 
   it "returns the location of the proc's body; not necessarily the proc itself" do
-    ProcSpecs::SourceLocation.my_detached_proc.source_location.last.should == 41
-    ProcSpecs::SourceLocation.my_detached_proc_new.source_location.last.should == 51
-    ProcSpecs::SourceLocation.my_detached_lambda.source_location.last.should == 46
+    ProcSpecs::SourceLocation.my_detached_proc.source_location.last.should == ProcSpecs::SourceLocation::MY_DETACHED_PROC_LINE
+    ProcSpecs::SourceLocation.my_detached_proc_new.source_location.last.should == ProcSpecs::SourceLocation::MY_DETACHED_PROC_NEW_LINE
+    ProcSpecs::SourceLocation.my_detached_lambda.source_location.last.should == ProcSpecs::SourceLocation::MY_DETACHED_LAMBDA_LINE
   end
 
   it "returns the same value for a proc-ified method as the method reports" do
diff --git a/spec/ruby/core/proc/source_range_spec.rb b/spec/ruby/core/proc/source_range_spec.rb
new file mode 100644
index 0000000000..81c803cc6b
--- /dev/null
+++ b/spec/ruby/core/proc/source_range_spec.rb
@@ -0,0 +1,146 @@
+require_relative '../../spec_helper'
+require_relative 'fixtures/source_range_helpers'
+
+ruby_version_is "4.1" do
+  describe "Proc#source_range" do
+    it "sets absolute_path to the real path of the source file" do
+      my_proc = proc {}
+      my_proc.source_range.absolute_path.should == File.realpath(__FILE__)
+    end
+
+    it "sets path to the source location path" do
+      my_proc = proc {}
+      my_proc.source_range.path.should == __FILE__
+    end
+
+    it "works for proc {}" do
+      check_source_range <<-RUBY
+      proc ${}$
+      RUBY
+    end
+
+    it "works for Proc.new {}" do
+      check_source_range <<-RUBY
+      Proc.new ${}$
+      RUBY
+    end
+
+    it "works for lambda {}" do
+      check_source_range <<-RUBY
+      lambda ${}$
+      RUBY
+    end
+
+    it "works for -> {}" do
+      check_source_range <<-RUBY
+      $-> {}$
+      RUBY
+    end
+
+    it "works with multibyte characters and return byte columns" do
+      check_source_range <<-RUBY
+      $-> (il, était, un) { été }$
+      RUBY
+    end
+
+    it "works for multi-line procs" do
+      check_source_range <<-RUBY
+      proc $do
+        'a'.upcase
+        1 + 22
+      end$
+      RUBY
+    end
+
+    it "works for returned blocks" do
+      check_source_range <<-RUBY
+      def return_block(&block)
+        block
+      end
+
+      return_block ${ 42 }$
+      RUBY
+    end
+
+    it "works for blocks passed to calls with receivers" do
+      check_source_range <<-RUBY
+      def block_receiver
+        obj = Object.new
+        def obj.foo(&block)
+          block
+        end
+        obj
+      end
+
+      block_receiver.foo ${ 42 }$
+      RUBY
+    end
+
+    it "uses the '}' as the end bound for a Proc with a heredoc inside" do
+      check_source_range <<-RUBY
+      proc ${ <<~END }$
+        heredoc
+      END
+      RUBY
+    end
+
+    it "works for for-loop body procs" do
+      check_source_range <<-RUBY
+      iter = Object.new
+      def iter.each(&block)
+        block.call(block)
+      end
+
+      $for pr in iter
+        42
+      end$
+
+      pr
+      RUBY
+    end
+
+    it "works for define_method & to_proc" do
+      check_source_range <<-RUBY
+      self.singleton_class.define_method :foo $do
+        1 + 2
+      end$
+
+      method(:foo).to_proc
+      RUBY
+    end
+
+    it "returns the same range for a proc-ified method as the method reports" do
+      def my_proc
+        proc { true }
+      end
+
+      meth = method(:my_proc)
+      proc = meth.to_proc
+
+      source_range_values(proc.source_range).should == source_range_values(meth.source_range)
+      proc.source_range.path.should == meth.source_range.path
+      proc.source_range.absolute_path.should == meth.source_range.absolute_path
+    end
+
+    it "returns nil for a core method that has been proc-ified" do
+      [].method(:<<).to_proc.source_range.should == nil
+    end
+
+    it "sets #path when #absolute_path is nil" do
+      range = eval('-> { 1 }', nil, "foo").source_range
+      range.path.should == "foo"
+      range.absolute_path.should == nil
+    end
+
+    it "sets #absolute_path to nil even if an absolute path is given to eval" do
+      range = eval('-> { 1 }', nil, "/foo").source_range
+      range.path.should == "/foo"
+      range.absolute_path.should == nil
+    end
+
+    it "considers eval's start line" do
+      range = eval('-> { 1 }', nil, "foo", 100).source_range
+      range.start_line.should == 100
+    end
+  end
+end
diff --git a/spec/ruby/core/ruby/source_range/inspect_spec.rb b/spec/ruby/core/ruby/source_range/inspect_spec.rb
new file mode 100644
index 0000000000..a23673397e
--- /dev/null
+++ b/spec/ruby/core/ruby/source_range/inspect_spec.rb
@@ -0,0 +1,18 @@
+require_relative '../../../spec_helper'
+
+ruby_version_is "4.1" do
+  describe "Ruby::SourceRange#inspect" do
+    it "includes the absolute path and coordinates" do
+      range = proc { 1 }.source_range
+
+      range.inspect.should == "#<Ruby::SourceRange #{range.absolute_path}:(#{range.start_line},#{range.start_column})-(#{range.end_line},#{range.end_column})>"
+    end
+
+    it "uses path when absolute_path is nil" do
+      range = eval('proc { 1 }', nil, "foo", 100).source_range
+
+      range.absolute_path.should == nil
+      range.inspect.should == "#<Ruby::SourceRange foo:(#{range.start_line},#{range.start_column})-(#{range.end_line},#{range.end_column})>"
+    end
+  end
+end
diff --git a/spec/ruby/core/unboundmethod/fixtures/classes.rb b/spec/ruby/core/unboundmethod/fixtures/classes.rb
index 58120c2f88..29d4902e50 100644
--- a/spec/ruby/core/unboundmethod/fixtures/classes.rb
+++ b/spec/ruby/core/unboundmethod/fixtures/classes.rb
@@ -1,19 +1,20 @@
 module UnboundMethodSpecs
-
-
   class SourceLocation
-    def self.location # This needs to be on this line
-      :location       # for the spec to pass
+    LOCATION_LINE = __LINE__ + 1
+    def self.location
+      :location
     end
 
     def self.redefined
       :first
     end
 
+    REDEFINED_LINE = __LINE__ + 1
     def self.redefined
       :last
     end
 
+    ORIGINAL_LINE = __LINE__ + 1
     def original
     end
 
diff --git a/spec/ruby/core/unboundmethod/source_location_spec.rb b/spec/ruby/core/unboundmethod/source_location_spec.rb
index 927600bfcb..8ed94a395e 100644
--- a/spec/ruby/core/unboundmethod/source_location_spec.rb
+++ b/spec/ruby/core/unboundmethod/source_location_spec.rb
@@ -15,15 +15,15 @@ describe "UnboundMethod#source_location" do
   it "sets the last value to an Integer representing the line on which the method was defined" do
     line = @method.source_location.last
     line.should.instance_of?(Integer)
-    line.should == 5
+    line.should == UnboundMethodSpecs::SourceLocation::LOCATION_LINE
   end
 
   it "returns the last place the method was defined" do
-    UnboundMethodSpecs::SourceLocation.method(:redefined).unbind.source_location.last.should == 13
+    UnboundMethodSpecs::SourceLocation.method(:redefined).unbind.source_location.last.should == UnboundMethodSpecs::SourceLocation::REDEFINED_LINE
   end
 
   it "returns the location of the original method even if it was aliased" do
-    UnboundMethodSpecs::SourceLocation.instance_method(:aka).source_location.last.should == 17
+    UnboundMethodSpecs::SourceLocation.instance_method(:aka).source_location.last.should == UnboundMethodSpecs::SourceLocation::ORIGINAL_LINE
   end
 
   it "works for define_method methods" do
diff --git a/spec/ruby/core/unboundmethod/source_range_spec.rb b/spec/ruby/core/unboundmethod/source_range_spec.rb
new file mode 100644
index 0000000000..9ae55daf59
--- /dev/null
+++ b/spec/ruby/core/unboundmethod/source_range_spec.rb
@@ -0,0 +1,12 @@
+require_relative '../../spec_helper'
+require_relative '../method/shared/source_range'
+
+ruby_version_is "4.1" do
+  describe "UnboundMethod#source_range" do
+    before :each do
+      @object = -> method { method.unbind }
+    end
+
+    it_behaves_like :method_source_range, :source_range
+  end
+end
diff --git a/template/fake.rb.in b/template/fake.rb.in
index fed640aee7..a2f90d677b 100644
--- a/template/fake.rb.in
+++ b/template/fake.rb.in
@@ -51,8 +51,8 @@ class Object
 end
 v=$VERBOSE;$VERBOSE=nil;module Ruby; end;$VERBOSE=v
 module Ruby
-  constants.each {|n| remove_const n}
 % arg['versions'].each {|n, v|
+  remove_const :<%=n%> if defined?(<%=n%>)
   <%=n%> = ::RUBY_<%=n%>
 % }
 end