simplebench: add img_bench_templater.py

Add simple grammar-parsing template benchmark. New tool consume test
template written in bash with some special grammar injections and
produces multiple tests, run them and finally print a performance
comparison table of different tests produced from one template.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210824101517.59802-2-vsementsov@virtuozzo.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>

scripts/simplebench/table_templater.py

@@ -0,0 +1,62 @@
+# Parser for test templates
+#
+# Copyright (c) 2021 Virtuozzo International GmbH.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+import itertools
+from lark import Lark
+
+grammar = """
+start: ( text | column_switch | row_switch )+
+
+column_switch: "{" text ["|" text]+ "}"
+row_switch: "[" text ["|" text]+ "]"
+text: /[^|{}\[\]]+/
+"""
+
+parser = Lark(grammar)
+
+class Templater:
+    def __init__(self, template):
+        self.tree = parser.parse(template)
+
+        c_switches = []
+        r_switches = []
+        for x in self.tree.children:
+            if x.data == 'column_switch':
+                c_switches.append([el.children[0].value for el in x.children])
+            elif x.data == 'row_switch':
+                r_switches.append([el.children[0].value for el in x.children])
+
+        self.columns = list(itertools.product(*c_switches))
+        self.rows = list(itertools.product(*r_switches))
+
+    def gen(self, column, row):
+        i = 0
+        j = 0
+        result = []
+
+        for x in self.tree.children:
+            if x.data == 'text':
+                result.append(x.children[0].value)
+            elif x.data == 'column_switch':
+                result.append(column[i])
+                i += 1
+            elif x.data == 'row_switch':
+                result.append(row[j])
+                j += 1
+
+        return ''.join(result)