merge revision(s) 44604,44605,44606: [Backport #9415]

	test_m17n.rb: split tests for inspect

	* test/ruby/test_m17n.rb (test_utf_16_32_inspect): split tests for
  each encodings.
	* string.c (get_actual_encoding): get actual encoding according to
	  the BOM if exists.

	* string.c (rb_str_inspect): use according encoding, instead of
	  pseudo encodings, UTF-{16,32}.  [ruby-core:59757] [Bug #8940]

	* string.c (get_encoding): respect BOM on pseudo encodings.
	  [ruby-dev:47895] [Bug #9415]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_1@45074 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 45 insertions, 24 deletions

diff --git a/string.c b/string.c
index cc307866db..983c2a1166 100644
--- a/string.c
+++ b/string.c
@@ -121,7 +121,45 @@ VALUE rb_cSymbol;
 #define STR_HEAP_PTR(str)  (RSTRING(str)->as.heap.ptr)
 #define STR_HEAP_SIZE(str) (RSTRING(str)->as.heap.aux.capa + TERM_LEN(str))
 
-#define STR_ENC_GET(str) rb_enc_from_index(ENCODING_GET(str))
+#define STR_ENC_GET(str) get_encoding(str)
+
+rb_encoding *rb_enc_get_from_index(int index);
+
+static rb_encoding *
+get_actual_encoding(const int encidx, VALUE str)
+{
+    const unsigned char *q;
+
+    switch (encidx) {
+      case ENCINDEX_UTF_16:
+	if (RSTRING_LEN(str) < 2) break;
+	q = (const unsigned char *)RSTRING_PTR(str);
+	if (q[0] == 0xFE && q[1] == 0xFF) {
+	    return rb_enc_get_from_index(ENCINDEX_UTF_16BE);
+	}
+	if (q[0] == 0xFF && q[1] == 0xFE) {
+	    return rb_enc_get_from_index(ENCINDEX_UTF_16LE);
+	}
+	return rb_ascii8bit_encoding();
+      case ENCINDEX_UTF_32:
+	if (RSTRING_LEN(str) < 4) break;
+	q = (const unsigned char *)RSTRING_PTR(str);
+	if (q[0] == 0 && q[1] == 0 && q[2] == 0xFE && q[3] == 0xFF) {
+	    return rb_enc_get_from_index(ENCINDEX_UTF_32BE);
+	}
+	if (q[3] == 0 && q[2] == 0 && q[1] == 0xFE && q[0] == 0xFF) {
+	    return rb_enc_get_from_index(ENCINDEX_UTF_32LE);
+	}
+	return rb_ascii8bit_encoding();
+    }
+    return rb_enc_from_index(encidx);
+}
+
+static rb_encoding *
+get_encoding(VALUE str)
+{
+    return get_actual_encoding(ENCODING_GET(str), str);
+}
 
 static int fstring_cmp(VALUE a, VALUE b);
 
@@ -4750,8 +4788,8 @@ rb_str_buf_cat_escaped_char(VALUE result, unsigned int c, int unicode_p)
 VALUE
 rb_str_inspect(VALUE str)
 {
-    rb_encoding *enc = STR_ENC_GET(str);
-    int encidx = rb_enc_to_index(enc);
+    int encidx = ENCODING_GET(str);
+    rb_encoding *enc = rb_enc_from_index(encidx), *actenc;
     const char *p, *pend, *prev;
     char buf[CHAR_ESC_LEN + 1];
     VALUE result = rb_str_buf_new(0);
@@ -4766,27 +4804,10 @@ rb_str_inspect(VALUE str)
 
     p = RSTRING_PTR(str); pend = RSTRING_END(str);
     prev = p;
-    if (encidx == ENCINDEX_UTF_16 && p + 2 <= pend) {
-	const unsigned char *q = (const unsigned char *)p;
-	if (q[0] == 0xFE && q[1] == 0xFF)
-	    enc = rb_enc_from_index(ENCINDEX_UTF_16BE);
-	else if (q[0] == 0xFF && q[1] == 0xFE)
-	    enc = rb_enc_from_index(ENCINDEX_UTF_16LE);
-	else {
-	    enc = rb_ascii8bit_encoding();
-	    unicode_p = 0;
-	}
-    }
-    else if (encidx == ENCINDEX_UTF_32 && p + 4 <= pend) {
-	const unsigned char *q = (const unsigned char *)p;
-	if (q[0] == 0 && q[1] == 0 && q[2] == 0xFE && q[3] == 0xFF)
-	    enc = rb_enc_from_index(ENCINDEX_UTF_32BE);
-	else if (q[3] == 0 && q[2] == 0 && q[1] == 0xFE && q[0] == 0xFF)
-	    enc = rb_enc_from_index(ENCINDEX_UTF_32LE);
-	else {
-	    enc = rb_ascii8bit_encoding();
-	    unicode_p = 0;
-	}
+    actenc = get_actual_encoding(encidx, str);
+    if (actenc != enc) {
+	enc = actenc;
+	if (unicode_p) unicode_p = rb_enc_unicode_p(enc);
     }
     while (p < pend) {
 	unsigned int c, cc;