From c34e9f23aa2b6909e92623710e91cd99eaff2dc3 Mon Sep 17 00:00:00 2001
From: marcandre <marcandre@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Tue, 29 Jan 2013 22:00:58 +0000
Subject: [PATCH] * object.c: Improve error for failed implicit conversions
 [Bug #7539]

* error.c: Adapt rdoc

* test/ruby/test_object.rb: Test for above

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38979 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog                | 8 ++++++++
 error.c                  | 2 +-
 object.c                 | 5 ++++-
 test/ruby/test_object.rb | 8 ++++++++
 4 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index d44d5c6c23..7e067a64ee 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Wed Jan 30 07:00:16 2013  Marc-Andre Lafortune  <ruby-core@marc-andre.ca>
+
+	* object.c: Improve error for failed implicit conversions [Bug #7539]
+
+	* error.c: Adapt rdoc
+
+	* test/ruby/test_object.rb: Test for above
+
 Tue Jan 29 21:40:12 2013  Tanaka Akira  <akr@fsij.org>
 
 	* lib/net/http/generic_request.rb (encode_multipart_form_data): remove
diff --git a/error.c b/error.c
index da24505eb0..4b678d8957 100644
--- a/error.c
+++ b/error.c
@@ -1390,7 +1390,7 @@ syserr_eqq(VALUE self, VALUE exc)
  *
  *  <em>raises the exception:</em>
  *
- *     TypeError: can't convert String into Integer
+ *     TypeError: no implicit conversion of String into Integer
  *
  */
 
diff --git a/object.c b/object.c
index 09b8040820..ba4f997b3a 100644
--- a/object.c
+++ b/object.c
@@ -2277,6 +2277,7 @@ static struct conv_method_tbl {
     {"to_s", 0},
     {NULL, 0}
 };
+#define IMPLICIT_CONVERSIONS 7
 
 static VALUE
 convert_type(VALUE val, const char *tname, const char *method, int raise)
@@ -2296,7 +2297,9 @@ convert_type(VALUE val, const char *tname, const char *method, int raise)
     r = rb_check_funcall(val, m, 0, 0);
     if (r == Qundef) {
 	if (raise) {
-	    rb_raise(rb_eTypeError, "can't convert %s into %s",
+	    rb_raise(rb_eTypeError, i < IMPLICIT_CONVERSIONS
+                ? "no implicit conversion of %s into %s"
+                : "can't convert %s into %s",
 		     NIL_P(val) ? "nil" :
 		     val == Qtrue ? "true" :
 		     val == Qfalse ? "false" :
diff --git a/test/ruby/test_object.rb b/test/ruby/test_object.rb
index 9f0e9bc5b2..9787525bce 100644
--- a/test/ruby/test_object.rb
+++ b/test/ruby/test_object.rb
@@ -885,4 +885,12 @@ class TestObject < Test::Unit::TestCase
     assert_not_initialize_copy {st.new}
     assert_not_initialize_copy {Time.now}
   end
+
+  def test_type_error_message
+    issue = "Bug #7539"
+    err = assert_raise(TypeError){ Integer([42]) }
+    assert_equal "can't convert Array into Integer", err.message, issue
+    err = assert_raise(TypeError){ [].first([42]) }
+    assert_equal 'no implicit conversion of Array into Integer', err.message, issue
+  end
 end