[makeotfexe] Add test case for bug 811

afdko issue "Bug in building MarkToBase lookup type 4" #811.

tests/makeotfexe_data/expected_output/bug811.ttx

@@ -0,0 +1,83 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ttFont sfntVersion="OTTO" ttLibVersion="3.43">
+
+  <GPOS>
+    <Version value="0x00010000"/>
+    <ScriptList>
+      <!-- ScriptCount=1 -->
+      <ScriptRecord index="0">
+        <ScriptTag value="DFLT"/>
+        <Script>
+          <DefaultLangSys>
+            <ReqFeatureIndex value="65535"/>
+            <!-- FeatureCount=1 -->
+            <FeatureIndex index="0" value="0"/>
+          </DefaultLangSys>
+          <!-- LangSysCount=0 -->
+        </Script>
+      </ScriptRecord>
+    </ScriptList>
+    <FeatureList>
+      <!-- FeatureCount=1 -->
+      <FeatureRecord index="0">
+        <FeatureTag value="GPS4"/>
+        <Feature>
+          <!-- LookupCount=1 -->
+          <LookupListIndex index="0" value="0"/>
+        </Feature>
+      </FeatureRecord>
+    </FeatureList>
+    <LookupList>
+      <!-- LookupCount=1 -->
+      <Lookup index="0">
+        <LookupType value="4"/>
+        <LookupFlag value="0"/>
+        <!-- SubTableCount=1 -->
+        <MarkBasePos index="0" Format="1">
+          <MarkCoverage Format="1">
+            <Glyph value=".notdef"/>
+            <Glyph value="a"/>
+          </MarkCoverage>
+          <BaseCoverage Format="1">
+            <Glyph value=".notdef"/>
+            <Glyph value="a"/>
+          </BaseCoverage>
+          <!-- ClassCount=1 -->
+          <MarkArray>
+            <!-- MarkCount=2 -->
+            <MarkRecord index="0">
+              <Class value="0"/>
+              <MarkAnchor Format="1">
+                <XCoordinate value="300"/>
+                <YCoordinate value="500"/>
+              </MarkAnchor>
+            </MarkRecord>
+            <MarkRecord index="1">
+              <Class value="0"/>
+              <MarkAnchor Format="1">
+                <XCoordinate value="300"/>
+                <YCoordinate value="680"/>
+              </MarkAnchor>
+            </MarkRecord>
+          </MarkArray>
+          <BaseArray>
+            <!-- BaseCount=2 -->
+            <BaseRecord index="0">
+              <BaseAnchor index="0" Format="1">
+                <XCoordinate value="300"/>
+                <YCoordinate value="680"/>
+              </BaseAnchor>
+            </BaseRecord>
+            <BaseRecord index="1">
+              <BaseAnchor index="0" Format="1">
+                <XCoordinate value="300"/>
+                <YCoordinate value="500"/>
+              </BaseAnchor>
+            </BaseRecord>
+          </BaseArray>
+        </MarkBasePos>
+      </Lookup>
+    </LookupList>
+  </GPOS>
+
+</ttFont>

tests/makeotfexe_data/input/bug811/feat.fea

@@ -0,0 +1,19 @@
+
+table head {
+	FontRevision 1.011;
+} head;
+
+languagesystem DFLT dflt;
+
+# Copeid loosely from SourceCodeProRegular
+@mGC_above_300_500 = [.notdef];
+@mGC_above_300_680 = [a];
+
+markClass @mGC_above_300_500 <anchor 300 500> @MC_above;
+markClass @mGC_above_300_680 <anchor 300 680> @MC_above;
+
+feature GPS4 {
+
+	pos base .notdef <anchor 300 680> mark @MC_above;
+	pos base a <anchor 300 500> mark @MC_above;
+} GPS4;

tests/makeotfexe_test.py

@@ -416,3 +416,16 @@ def test_parameter_offset_overflow_bug746():
     with open(stderr_path, 'rb') as f:
         output = f.read()
     assert(b"[FATAL] <bug746> feature parameter offset too large") in output
+
+
+def test_base_anchor_bug811():
+    input_filename = "bug811/font.pfa"
+    feat_filename = get_input_path('bug811/feat.fea')
+    actual_path = get_temp_file_path()
+    ttx_filename = "bug811.ttx"
+    runner(CMD + ['-o', 'f', '_{}'.format(get_input_path(input_filename)),
+                        'ff', '_{}'.format(get_input_path(feat_filename)),
+                        'o', '_{}'.format(actual_path)])
+    actual_ttx = generate_ttx_dump(actual_path, ['GPOS'])
+    expected_ttx = get_expected_path(ttx_filename)
+    assert differ([expected_ttx, actual_ttx, '-s', '<ttFont sfntVersion'])