From 0eafdef9881c396ce4c014359d8f497cc088cfab Mon Sep 17 00:00:00 2001
From: Daniel Veillard <veillard@src.gnome.org>
Date: Wed, 10 Apr 2002 16:14:34 +0000
Subject: [PATCH] another patch from Richard Jinks for substring conformance
 update of the

* xpath.c: another patch from Richard Jinks for substring conformance
* test/XPath/expr/floats test/XPath/expr/strings
  result/XPath/expr/floats result/XPath/expr/strings: update of the
  test suite to check those.
Daniel
---
 ChangeLog                 |  7 +++++
 result/XPath/expr/floats  |  8 ++++++
 result/XPath/expr/strings | 16 ++++++++++++
 test/XPath/expr/floats    |  2 ++
 test/XPath/expr/strings   |  4 +++
 xpath.c                   | 54 +++++++++++++++++++++++----------------
 6 files changed, 69 insertions(+), 22 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index a1df7564..44de2b7d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Wed Apr 10 18:12:52 CEST 2002 Daniel Veillard <daniel@veillard.com>
+
+	* xpath.c: another patch from Richard Jinks for substring conformance
+	* test/XPath/expr/floats test/XPath/expr/strings
+	  result/XPath/expr/floats result/XPath/expr/strings: update of the
+	  test suite to check those.
+
 Wed Apr 10 13:29:49 CEST 2002 Daniel Veillard <daniel@veillard.com>
 
 	* xpath.c: patch from Richard Jinks for .x float parsing.
diff --git a/result/XPath/expr/floats b/result/XPath/expr/floats
index 7a44f8df..176081b5 100644
--- a/result/XPath/expr/floats
+++ b/result/XPath/expr/floats
@@ -15,6 +15,14 @@ Object is a number : 1.23
 Expression: 0.123
 Object is a number : 0.123
 
+========================
+Expression: 4.
+Object is a number : 4
+
+========================
+Expression: .4
+Object is a number : 0.4
+
 ========================
 Expression: 1.23e3
 Object is a number : 1230
diff --git a/result/XPath/expr/strings b/result/XPath/expr/strings
index 09ccdec0..5ccd7c26 100644
--- a/result/XPath/expr/strings
+++ b/result/XPath/expr/strings
@@ -75,6 +75,22 @@ Object is a string : 234
 Expression: substring("12345",0,3)
 Object is a string : 12
 
+========================
+Expression: substring("12345", 0 div 0, 3)
+Object is a string : 
+
+========================
+Expression: substring("12345", 1, 0 div 0)
+Object is a string : 
+
+========================
+Expression: substring("12345", -42, 1 div 0)
+Object is a string : 12345
+
+========================
+Expression: substring("12345", -1 div 0, 1 div 0)
+Object is a string : 
+
 ========================
 Expression: string-length("")
 Object is a number : 0
diff --git a/test/XPath/expr/floats b/test/XPath/expr/floats
index 00ac6573..5d052d6a 100644
--- a/test/XPath/expr/floats
+++ b/test/XPath/expr/floats
@@ -2,6 +2,8 @@
 123
 1.23
 0.123
+4.
+.4
 1.23e3
 1.23e-3
 1 div 0
diff --git a/test/XPath/expr/strings b/test/XPath/expr/strings
index c54cdf33..a070f3a3 100644
--- a/test/XPath/expr/strings
+++ b/test/XPath/expr/strings
@@ -17,5 +17,9 @@ substring("12345",2,3)
 substring("12345",2)
 substring("12345",1.5,2.6)
 substring("12345",0,3)
+substring("12345", 0 div 0, 3)
+substring("12345", 1, 0 div 0)
+substring("12345", -42, 1 div 0)
+substring("12345", -1 div 0, 1 div 0)
 string-length("")
 string-length("titi")
diff --git a/xpath.c b/xpath.c
index 9de5bc9d..ad9c3ef8 100644
--- a/xpath.c
+++ b/xpath.c
@@ -6152,34 +6152,44 @@ xmlXPathSubstringFunction(xmlXPathParserContextPtr ctxt, int nargs) {
     if (nargs != 3)
 	le = m;
 
-    /*
-     * To meet our requirements, initial index calculations
-     * must be done before we convert to integer format
-     *
-     * First we normalize indices
+    /* Need to check for the special cases where either 
+     * the index is NaN, the length is NaN, or both
+     * arguments are infinity (relying on Inf + -Inf = NaN)
      */
-    in -= 1.0;
-    le += in;
-    if (in < 0.0)
-	in = 0.0;
-    if (le > (double)m)
-	le = (double)m;
+    if (!xmlXPathIsNaN(in + le)) {
+        /*
+         * To meet our requirements, initial index calculations
+         * must be done before we convert to integer format
+         *
+         * First we normalize indices
+         */
+        in -= 1.0;
+        le += in;
+        if (in < 0.0)
+            in = 0.0;
+        if (le > (double)m)
+            le = (double)m;
 
-    /*
-     * Now we go to integer form, rounding up
-     */
-    i = (int) in;
-    if (((double)i) != in) i++;
+        /*
+         * Now we go to integer form, rounding up
+         */
+        i = (int) in;
+        if (((double)i) != in) i++;
     
-    l = (int) le;
-    if (((double)l) != le) l++;
+        l = (int) le;
+        if (((double)l) != le) l++;
 
-    if (l > m) l=m;
+        if (l > m) l=m;
 
-    /* number of chars to copy */
-    l -= i;
+        /* number of chars to copy */
+        l -= i;
+
+        ret = xmlUTF8Strsub(str->stringval, i, l);
+    }
+    else {
+        ret = NULL;
+    }
 
-    ret = xmlUTF8Strsub(str->stringval, i, l);
     if (ret == NULL)
 	valuePush(ctxt, xmlXPathNewCString(""));
     else {