Add collation_order() ICU function

src/calibre/utils/icu.c

@@ -4,6 +4,7 @@
 #include <unicode/utypes.h>
 #include <unicode/uclean.h>
 #include <unicode/ucol.h>
+#include <unicode/ucoleitr.h>
 #include <unicode/ustring.h>
 #include <unicode/usearch.h>
 
@@ -310,6 +311,41 @@ icu_Collator_startswith(icu_Collator *self, PyObject *args, PyObject *kwargs) {
     Py_RETURN_FALSE;
 } // }}}
 
+// Collator.startswith {{{
+static PyObject *
+icu_Collator_collation_order(icu_Collator *self, PyObject *args, PyObject *kwargs) {
+    PyObject *a_;
+    size_t asz;
+    int32_t actual_a;
+    UChar *a;
+    wchar_t *aw;
+    UErrorCode status = U_ZERO_ERROR;
+    UCollationElements *iter = NULL;
+    int order = 0, len = -1;
+  
+    if (!PyArg_ParseTuple(args, "U", &a_)) return NULL;
+    asz = PyUnicode_GetSize(a_); 
+    
+    a = (UChar*)calloc(asz*4 + 2, sizeof(UChar));
+    aw = (wchar_t*)calloc(asz*4 + 2, sizeof(wchar_t));
+
+    if (a == NULL || aw == NULL ) return PyErr_NoMemory();
+
+    actual_a = (int32_t)PyUnicode_AsWideChar((PyUnicodeObject*)a_, aw, asz*4+1);
+    if (actual_a > -1) {
+        u_strFromWCS(a, asz*4 + 1, &actual_a, aw, -1, &status);
+        iter = ucol_openElements(self->collator, a, actual_a, &status);
+        if (iter != NULL && U_SUCCESS(status)) {
+            order = ucol_next(iter, &status);
+            len = ucol_getOffset(iter);
+            ucol_closeElements(iter); iter = NULL;
+        }
+    }
+
+    free(a); free(aw); 
+    return Py_BuildValue("ii", order, len);
+} // }}}
+
 static PyObject*
 icu_Collator_clone(icu_Collator *self, PyObject *args, PyObject *kwargs);
 
@@ -338,6 +374,10 @@ static PyMethodDef icu_Collator_methods[] = {
         "startswith(a, b) -> returns True iff a startswith b, following the current collation rules."
     },
 
+    {"collation_order", (PyCFunction)icu_Collator_collation_order, METH_VARARGS,
+        "collation_order(string) -> returns (order, length) where order is an integer that gives the position of string in a list. length gives the number of characters used for order."
+    },
+
     {NULL}  /* Sentinel */
 };
 

src/calibre/utils/icu.py

@@ -75,6 +75,7 @@ def icu_sort_key(collator, obj):
     except AttributeError:
         return secondary_collator().sort_key(obj)
 
+
 def py_find(pattern, source):
     pos = source.find(pattern)
     if pos > -1:
@@ -126,6 +127,12 @@ def icu_contractions(collator):
         _cmap[collator] = ans
     return ans
 
+def icu_collation_order(collator, a):
+    try:
+        return collator.collation_order(a)
+    except TypeError:
+        return collator.collation_order(unicode(a))
+
 load_icu()
 load_collator()
 _icu_not_ok = _icu is None or _collator is None
@@ -205,6 +212,14 @@ def primary_startswith(a, b):
     except AttributeError:
         return icu_startswith(primary_collator(), a, b)
 
+def collation_order(a):
+    if _icu_not_ok:
+        return (ord(a[0]), 1) if a else (0, 0)
+    try:
+        return icu_collation_order(_secondary_collator, a)
+    except AttributeError:
+        return icu_collation_order(secondary_collator(), a)
+
 ################################################################################
 
 def test(): # {{{