Handle numbering levels defined without an index

5 files changed, 99 insertions, 8 deletions

diff --git a/NEWS b/NEWS
index 9fd5547..65daefc 100644
--- a/NEWS
+++ b/NEWS
@@ -4,6 +4,8 @@
 
 * Support disabling external file accesses using the externalFileAccess option.
 
+* Handle numbering levels defined without an index.
+
 # 1.10.0
 
 * Add "Heading" and "Body" styles, as found in documents created by Apple Pages,
diff --git a/lib/docx/body-reader.js b/lib/docx/body-reader.js
index 5cdb4ef..826424b 100644
--- a/lib/docx/body-reader.js
+++ b/lib/docx/body-reader.js
@@ -670,6 +670,13 @@ function readNumberingProperties(styleId, element, numbering) {
         }
     }
 
+    // Some malformed documents define numbering levels without an index, and
+    // reference the numbering using a w:numPr element without a w:ilvl child.
+    // To handle such cases, we assume a level of 0 as a fallback.
+    if (numId !== undefined) {
+        return numbering.findLevel(numId, "0");
+    }
+
     return null;
 }
 
diff --git a/lib/docx/numbering-xml.js b/lib/docx/numbering-xml.js
index 7e368ac..c41477e 100644
--- a/lib/docx/numbering-xml.js
+++ b/lib/docx/numbering-xml.js
@@ -64,18 +64,37 @@ function readAbstractNums(root) {
 
 function readAbstractNum(element) {
     var levels = {};
+
+    // Some malformed documents define numbering levels without an index, and
+    // reference the numbering using a w:numPr element without a w:ilvl child.
+    // To handle such cases, we assume a level of 0 as a fallback.
+    var levelWithoutIndex = null;
+
     element.getElementsByTagName("w:lvl").forEach(function(levelElement) {
         var levelIndex = levelElement.attributes["w:ilvl"];
         var numFmt = levelElement.firstOrEmpty("w:numFmt").attributes["w:val"];
+        var isOrdered = numFmt !== "bullet";
         var paragraphStyleId = levelElement.firstOrEmpty("w:pStyle").attributes["w:val"];
 
-        levels[levelIndex] = {
-            isOrdered: numFmt !== "bullet",
-            level: levelIndex,
-            paragraphStyleId: paragraphStyleId
-        };
+        if (levelIndex === undefined) {
+            levelWithoutIndex = {
+                isOrdered: isOrdered,
+                level: "0",
+                paragraphStyleId: paragraphStyleId
+            };
+        } else {
+            levels[levelIndex] = {
+                isOrdered: isOrdered,
+                level: levelIndex,
+                paragraphStyleId: paragraphStyleId
+            };
+        }
     });
 
+    if (levels["0"] === undefined && levelWithoutIndex !== null) {
+        levels["0"] = levelWithoutIndex;
+    }
+
     var numStyleLink = element.firstOrEmpty("w:numStyleLink").attributes["w:val"];
 
     return {levels: levels, numStyleLink: numStyleLink};
diff --git a/test/docx/body-reader.tests.js b/test/docx/body-reader.tests.js
index 4fbea03..de7af2d 100644
--- a/test/docx/body-reader.tests.js
+++ b/test/docx/body-reader.tests.js
@@ -223,17 +223,17 @@ test("numbering properties are converted to numbering at specified level", funct
     assert.deepEqual(numberingLevel, {level: "1", isOrdered: true});
 });
 
-test("numbering properties are ignored if w:ilvl is missing", function() {
+test("when numbering properties are missing w:ilvl then level of 0 is assumed", function() {
     var numberingPropertiesXml = new XmlElement("w:numPr", {}, [
         new XmlElement("w:numId", {"w:val": "42"})
     ]);
 
     var numbering = new NumberingMap({
-        findLevel: {"42": {"1": {isOrdered: true, level: "1"}}}
+        findLevel: {"42": {"0": {isOrdered: true, level: "0"}}}
     });
 
     var numberingLevel = _readNumberingProperties(null, numberingPropertiesXml, numbering);
-    assert.equal(numberingLevel, null);
+    assert.deepEqual(numberingLevel, {level: "0", isOrdered: true});
 });
 
 test("numbering properties are ignored if w:numId is missing", function() {
diff --git a/test/docx/numbering-xml.tests.js b/test/docx/numbering-xml.tests.js
index a648349..004e9ab 100644
--- a/test/docx/numbering-xml.tests.js
+++ b/test/docx/numbering-xml.tests.js
@@ -45,6 +45,69 @@ test('w:num element referencing non-existent w:abstractNumId is ignored', functi
     duck.assertThat(numbering.findLevel("47", "0"), duck.equalTo(null));
 });
 
+test('given no other levels with index of 0 when level is missing w:ilvl then level index is 0', function() {
+    var numbering = readNumberingXml(
+        new XmlElement("w:numbering", {}, [
+            new XmlElement("w:abstractNum", {"w:abstractNumId": "42"}, [
+                new XmlElement("w:lvl", {}, [
+                    new XmlElement("w:numFmt", {"w:val": "decimal"})
+                ])
+            ]),
+            new XmlElement("w:num", {"w:numId": "47"}, [
+                new XmlElement("w:abstractNumId", {"w:val": "42"})
+            ])
+        ]),
+        {styles: stylesReader.defaultStyles}
+    );
+    duck.assertThat(numbering.findLevel("47", "0"), duck.hasProperties({
+        isOrdered: true
+    }));
+});
+
+test('given previous other level with index of 0 when level is missing w:ilvl then level is ignored', function() {
+    var numbering = readNumberingXml(
+        new XmlElement("w:numbering", {}, [
+            new XmlElement("w:abstractNum", {"w:abstractNumId": "42"}, [
+                new XmlElement("w:lvl", {"w:ilvl": "0"}, [
+                    new XmlElement("w:numFmt", {"w:val": "bullet"})
+                ]),
+                new XmlElement("w:lvl", {}, [
+                    new XmlElement("w:numFmt", {"w:val": "decimal"})
+                ])
+            ]),
+            new XmlElement("w:num", {"w:numId": "47"}, [
+                new XmlElement("w:abstractNumId", {"w:val": "42"})
+            ])
+        ]),
+        {styles: stylesReader.defaultStyles}
+    );
+    duck.assertThat(numbering.findLevel("47", "0"), duck.hasProperties({
+        isOrdered: false
+    }));
+});
+
+test('given subsequent other level with index of 0 when level is missing w:ilvl then level is ignored', function() {
+    var numbering = readNumberingXml(
+        new XmlElement("w:numbering", {}, [
+            new XmlElement("w:abstractNum", {"w:abstractNumId": "42"}, [
+                new XmlElement("w:lvl", {}, [
+                    new XmlElement("w:numFmt", {"w:val": "decimal"})
+                ]),
+                new XmlElement("w:lvl", {"w:ilvl": "0"}, [
+                    new XmlElement("w:numFmt", {"w:val": "bullet"})
+                ])
+            ]),
+            new XmlElement("w:num", {"w:numId": "47"}, [
+                new XmlElement("w:abstractNumId", {"w:val": "42"})
+            ])
+        ]),
+        {styles: stylesReader.defaultStyles}
+    );
+    duck.assertThat(numbering.findLevel("47", "0"), duck.hasProperties({
+        isOrdered: false
+    }));
+});
+
 test('when level is missing w:numFmt then level is ordered', function() {
     var numbering = readNumberingXml(
         new XmlElement("w:numbering", {}, [