From 2451f8085be6ced9ac8e5b2595e0b43bf50599d9 Mon Sep 17 00:00:00 2001
From: Pavel Tyunin <pavel51tunin@gmail.com>
Date: Thu, 25 Feb 2021 21:23:33 +0200
Subject: [PATCH] Fix search in wxSortedArrayString with custom compare
 function

---
 include/wx/arrstr.h     |  3 ++
 src/common/arrstr.cpp   | 70 ++++++++++++++++-------------------------
 tests/arrays/arrays.cpp |  5 +++
 3 files changed, 35 insertions(+), 43 deletions(-)

diff --git a/include/wx/arrstr.h b/include/wx/arrstr.h
index e21dc78761..bed1098d74 100644
--- a/include/wx/arrstr.h
+++ b/include/wx/arrstr.h
@@ -398,6 +398,9 @@ private:
   // (if the old buffer is big enough, just return NULL).
   wxString *Grow(size_t nIncrement);
 
+  // Binary search in the sorted array
+  size_t BinarySearch(const wxString& str, bool equal = false) const;
+
   size_t  m_nSize,    // current size of the array
           m_nCount;   // current number of elements
 
diff --git a/src/common/arrstr.cpp b/src/common/arrstr.cpp
index dc569a80bf..3aac42f67d 100644
--- a/src/common/arrstr.cpp
+++ b/src/common/arrstr.cpp
@@ -377,6 +377,29 @@ void wxArrayString::Shrink()
   }
 }
 
+// Binary search in the sorted array
+size_t wxArrayString::BinarySearch(const wxString& str, bool equal) const
+{
+    size_t
+        lo = 0,
+        hi = m_nCount;
+    while (lo < hi) {
+        size_t i;
+        i = (lo + hi) / 2;
+
+        int res;
+        res = m_compareFunction ? m_compareFunction(str, m_pItems[i]) : str.Cmp(m_pItems[i]);
+        if (res < 0)
+            hi = i;
+        else if (res > 0)
+            lo = i + 1;
+        else
+            return i;
+    }
+    wxASSERT_MSG(lo == hi, wxT("binary search broken"));
+    return equal ? wxNOT_FOUND : lo;
+}
+
 // searches the array for an item (forward or backwards)
 int wxArrayString::Index(const wxString& str, bool bCase, bool bFromEnd) const
 {
@@ -384,25 +407,7 @@ int wxArrayString::Index(const wxString& str, bool bCase, bool bFromEnd) const
     // use binary search in the sorted array
     wxASSERT_MSG( bCase && !bFromEnd,
                   wxT("search parameters ignored for auto sorted array") );
-
-    size_t
-           lo = 0,
-           hi = m_nCount;
-    while ( lo < hi ) {
-      size_t i;
-      i = (lo + hi)/2;
-
-      int res;
-      res = str.compare(m_pItems[i]);
-      if ( res < 0 )
-        hi = i;
-      else if ( res > 0 )
-        lo = i + 1;
-      else
-        return i;
-    }
-
-    return wxNOT_FOUND;
+    return BinarySearch(str, true);
   }
   else {
     // use linear search in unsorted array
@@ -432,30 +437,9 @@ size_t wxArrayString::Add(const wxString& str, size_t nInsert)
 {
   if ( m_autoSort ) {
     // insert the string at the correct position to keep the array sorted
-    size_t
-           lo = 0,
-           hi = m_nCount;
-    while ( lo < hi ) {
-      size_t i;
-      i = (lo + hi)/2;
-
-      int res;
-      res = m_compareFunction ? m_compareFunction(str, m_pItems[i]) : str.Cmp(m_pItems[i]);
-      if ( res < 0 )
-        hi = i;
-      else if ( res > 0 )
-        lo = i + 1;
-      else {
-        lo = hi = i;
-        break;
-      }
-    }
-
-    wxASSERT_MSG( lo == hi, wxT("binary search broken") );
-
-    Insert(str, lo, nInsert);
-
-    return (size_t)lo;
+    size_t nIndex = BinarySearch(str);
+    Insert(str, nIndex, nInsert);
+    return nIndex;
   }
   else {
     // Now that we must postpone freeing the old memory until we don't need it
diff --git a/tests/arrays/arrays.cpp b/tests/arrays/arrays.cpp
index 3f61c4ff41..6c815eb52f 100644
--- a/tests/arrays/arrays.cpp
+++ b/tests/arrays/arrays.cpp
@@ -399,6 +399,11 @@ void ArraysTestCase::SortedArray()
     ad.Add("Aa");
     CPPUNIT_ASSERT_EQUAL( "a", ad[0] );
     CPPUNIT_ASSERT_EQUAL( "Aa", ad[1] );
+    CPPUNIT_ASSERT_EQUAL( 0, ad.Index("a") );
+    CPPUNIT_ASSERT_EQUAL( 1, ad.Index("Aa") );
+    CPPUNIT_ASSERT_EQUAL( 2, ad.Index("AB") );
+    CPPUNIT_ASSERT_EQUAL( wxNOT_FOUND, ad.Index("A") );
+    CPPUNIT_ASSERT_EQUAL( wxNOT_FOUND, ad.Index("z") );
 }
 
 void ArraysTestCase::wxStringArraySplitTest()