#1 inject tau

src/main/java/org/polystat/far/Reverses.java

@@ -84,6 +84,7 @@ public Collection<String> errors(final String locator) throws IOException {
         new Xsline(obj, new OutputTo(baos), new Spy.Verbose(), new ListOf<>())
             .with(Reverses.xsl("expected.xsl").with("expected", "\\perp"))
             .with(Reverses.xsl("reverses.xsl"))
+            .with(Reverses.xsl("inject-tau-numbers.xsl"))
             .with(
                 Reverses.xsl("calculate.xsl").with(
                     (href, base) -> new StreamSource(

src/main/resources/org/polystat/far/inject-tau-numbers.xsl

@@ -0,0 +1,40 @@
+<?xml version="1.0"?>
+<!--
+The MIT License (MIT)
+
+Copyright (c) 2020-2021 Polystat.org
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included
+in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+-->
+<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" id="inject-tau-numbers" version="2.0">
+  <xsl:strip-space elements="*"/>
+  <xsl:template match="r[not(@tau)]">
+    <xsl:copy>
+      <xsl:attribute name="tau">
+        <xsl:value-of select="count(./preceding::*) + count(ancestor::*) + 1"/>
+      </xsl:attribute>
+      <xsl:apply-templates select="node()|@*"/>
+    </xsl:copy>
+  </xsl:template>
+  <xsl:template match="node()|@*">
+    <xsl:copy>
+      <xsl:apply-templates select="node()|@*"/>
+    </xsl:copy>
+  </xsl:template>
+</xsl:stylesheet>

src/main/resources/org/polystat/far/reverses.xsl

@@ -34,7 +34,6 @@ SOFTWARE.
         <xsl:element name="r">
           <xsl:attribute name="f" select="$o/@base"/>
           <xsl:attribute name="pos" select="position()"/>
-          <xsl:attribute name="tau" select="$o/@line"/>
           <xsl:copy-of select="$result"/>
         </xsl:element>
       </xsl:variable>

src/test/java/org/polystat/far/ReversesTest.java

@@ -54,7 +54,10 @@ public void findsReversesInSimpleXml() throws Exception {
         final Path temp = Files.createTempDirectory("temp");
         final Reverses reverses = new Reverses(new XMIR(sources, temp));
         final Collection<String> bugs = reverses.errors("\\Phi.foo");
-        MatcherAssert.assertThat(bugs, Matchers.not(Matchers.emptyIterable()));
+        MatcherAssert.assertThat(
+            bugs,
+            Matchers.iterableWithSize(Matchers.not(Matchers.greaterThan(3)))
+        );
         Logger.debug(this, "Bugs found: %s", bugs);
     }
 

src/test/resources/org/polystat/tests/div-by-zero.eo

@@ -2,12 +2,7 @@
 
 [a b] > foo
   add. > @
+    div. a b
     div.
+      div. b a
       a
-      b
-    div.
-      div.
-        b
-        a
-      a
-