Filter: Allow 'size' accessor to be used in IF statements

Author: shahramn

src/grib_expression_class_functor.cc

@@ -92,6 +92,19 @@ static int evaluate_long(grib_expression* g, grib_handle* h, long* lres)
         return ret;
     }
 
+    if (STR_EQUAL(e->name, "size")) {
+        *lres = 0;
+        const char* p = grib_arguments_get_name(h, e->args, 0);
+        if (p) {
+            size_t size = 0;
+            int err = grib_get_size(h, p, &size);
+            if (err) return err;
+            *lres = (long)size;
+            return GRIB_SUCCESS;
+        }
+        return GRIB_INVALID_ARGUMENT;
+    }
+
     if (STR_EQUAL(e->name, "missing")) {
         const char* p = grib_arguments_get_name(h, e->args, 0);
         if (p) {

tests/CMakeLists.txt

@@ -104,6 +104,7 @@ if( HAVE_BUILD_TOOLS )
         grib_ifsParam
         grib_packing_order
         filter_substr
+        filter_size
         filter_is_in_list
         filter_transient_darray
         grib_uerra

tests/filter_size.sh

@@ -0,0 +1,33 @@
+#!/bin/sh
+# (C) Copyright 2005- ECMWF.
+#
+# This software is licensed under the terms of the Apache Licence Version 2.0
+# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
+# 
+# In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
+# virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
+#
+
+. ./include.ctest.sh
+
+label="filter_size_test"
+tempFilt=temp.$label.filt
+tempOut=temp.$label.txt
+
+cat > $tempFilt <<EOF
+  if (size(pl) == 64) {
+    print "size of pl is 64";
+  }
+  if (size(pl) == 128) {
+    print "size of pl is 128";
+  }
+EOF
+
+${tools_dir}/grib_filter $tempFilt $ECCODES_SAMPLES_PATH/reduced_gg_pl_32_grib2.tmpl > $tempOut
+grep "size of pl is 64" $tempOut
+
+${tools_dir}/grib_filter $tempFilt $ECCODES_SAMPLES_PATH/reduced_gg_pl_64_grib2.tmpl > $tempOut
+grep "size of pl is 128" $tempOut
+
+# Clean up
+rm -f $tempFilt $tempOut