Produce nicer error messages in C#

8 files changed, 61 insertions, 19 deletions

diff --git a/couscous.json b/couscous.json
index f478d4b..e628c14 100644
--- a/couscous.json
+++ b/couscous.json
@@ -8,6 +8,8 @@
     "!src/main/java/org/zwobble/mammoth/DocumentConverter.java",
     "!src/main/java/org/zwobble/mammoth/internal/docx/ZippedDocxFile.java",
     "!src/main/java/org/zwobble/mammoth/internal/docx/InMemoryDocxFile.java",
+    "!src/main/java/org/zwobble/mammoth/internal/styles/parsing/LineParseException.java",
+    "!src/main/java/org/zwobble/mammoth/internal/styles/parsing/ParseException.java",
     "!src/main/java/org/zwobble/mammoth/internal/util",
     "src/main/java/org/zwobble/mammoth/internal/util/InputStreamSupplier.java",
     "src/main/java/org/zwobble/mammoth/internal/util/Optionals.java",
diff --git a/dotnet/Mammoth.Tests/DocumentConverterTests.cs b/dotnet/Mammoth.Tests/DocumentConverterTests.cs
index 89ade1c..92a3adf 100644
--- a/dotnet/Mammoth.Tests/DocumentConverterTests.cs
+++ b/dotnet/Mammoth.Tests/DocumentConverterTests.cs
@@ -151,13 +151,24 @@ namespace Mammoth.Tests {
         }
 
         [Fact]
-        public void RulesFromPreviouslyAddedStyleMapsStillTakeEffectIfNotOverriden() {
+        public void RulesFromPreviouslyAddedStyleMapsStillTakeEffectIfNotOverridden() {
             AssertSuccessfulConversion(
                 ConvertToHtml("underline.docx", mammoth => mammoth.AddStyleMap("u => em").AddStyleMap("strike => del")),
                 "<p><strong>The <em>Sunset</em> Tree</strong></p>");
         }
 
         [Fact]
+        public void ErrorIsRaisedIfStyleMapCannotBeParsed() {
+	    var exception = Assert.ThrowsAny<Exception>(() =>
+		new DocumentConverter().AddStyleMap("p =>\np[style-name=] =>"));
+	    Assert.Equal(
+		"error reading style map at line 2, character 14: expected token of type _STRING but was of type _CLOSE_SQUARE_BRACKET\n\n" +
+                "p[style-name=] =>\n" +
+                "             ^",
+		exception.Message);
+        }
+
+        [Fact]
         public void CanDisableDefaultStyleMap() {
             var result = ConvertToHtml("simple-list.docx", mammoth => mammoth.DisableDefaultStyleMap());
             Assert.Equal(new[]{"Unrecognised paragraph style: List Paragraph (Style ID: ListParagraph)"}, result.Warnings);
diff --git a/dotnet/Mammoth/Couscous/HorribleHacks.cs b/dotnet/Mammoth/Couscous/HorribleHacks.cs
index 9f1ac30..c97dc0a 100644
--- a/dotnet/Mammoth/Couscous/HorribleHacks.cs
+++ b/dotnet/Mammoth/Couscous/HorribleHacks.cs
@@ -26,5 +26,9 @@ namespace Mammoth.Couscous {
         internal static bool equals(this TokenType first, TokenType second) {
             return first == second;
         }
+        
+        internal static string getMessage(this System.Exception exception) {
+            return exception.Message;
+        }
     }
 }
diff --git a/dotnet/Mammoth/Couscous/mammoth/internal/styles/parsing/LineParseException.cs b/dotnet/Mammoth/Couscous/mammoth/internal/styles/parsing/LineParseException.cs
new file mode 100644
index 0000000..6ca9381
--- /dev/null
+++ b/dotnet/Mammoth/Couscous/mammoth/internal/styles/parsing/LineParseException.cs
@@ -0,0 +1,15 @@
+using Mammoth.Couscous.java.lang;
+
+namespace Mammoth.Couscous.org.zwobble.mammoth.@internal.styles.parsing {
+    internal class LineParseException : RuntimeException {
+        private readonly Token _token;
+        
+        internal LineParseException(Token token, string message) : base(message) {
+            _token = token;
+        }
+        
+        internal Token getToken() {
+            return _token;
+        }
+    }
+}
diff --git a/dotnet/Mammoth/Couscous/mammoth/internal/styles/parsing/ParseException.cs b/dotnet/Mammoth/Couscous/mammoth/internal/styles/parsing/ParseException.cs
new file mode 100644
index 0000000..73f349c
--- /dev/null
+++ b/dotnet/Mammoth/Couscous/mammoth/internal/styles/parsing/ParseException.cs
@@ -0,0 +1,8 @@
+using Mammoth.Couscous.java.lang;
+
+namespace Mammoth.Couscous.org.zwobble.mammoth.@internal.styles.parsing {
+    internal class ParseException : RuntimeException {
+        internal ParseException(string message) : base(message) {
+        }
+    }
+}
diff --git a/dotnet/Mammoth/Mammoth.csproj b/dotnet/Mammoth/Mammoth.csproj
index 4e945d0..6e2c473 100644
--- a/dotnet/Mammoth/Mammoth.csproj
+++ b/dotnet/Mammoth/Mammoth.csproj
@@ -81,6 +81,8 @@
     <Compile Include="Couscous\java\util\Set.cs" />
     <Compile Include="Couscous\mammoth\internal\docx\InMemoryDocxFile.cs" />
     <Compile Include="Couscous\mammoth\internal\docx\ZippedDocxFile.cs" />
+    <Compile Include="Couscous\mammoth\internal\styles\parsing\LineParseException.cs" />
+    <Compile Include="Couscous\mammoth\internal\styles\parsing\ParseException.cs" />
     <Compile Include="Couscous\mammoth\internal\util\Base64Encoding.cs" />
     <Compile Include="Couscous\mammoth\internal\util\Casts.cs" />
     <Compile Include="Couscous\mammoth\internal\util\Lists.cs" />
diff --git a/src/main/java/org/zwobble/mammoth/internal/styles/parsing/ParseException.java b/src/main/java/org/zwobble/mammoth/internal/styles/parsing/ParseException.java
index 40fb16b..718bb30 100644
--- a/src/main/java/org/zwobble/mammoth/internal/styles/parsing/ParseException.java
+++ b/src/main/java/org/zwobble/mammoth/internal/styles/parsing/ParseException.java
@@ -1,22 +1,7 @@
 package org.zwobble.mammoth.internal.styles.parsing;
 
 public class ParseException extends RuntimeException {
-    public ParseException(String line, int lineNumber, Token token, String message) {
-        super(generateMessage(line, lineNumber, token, message));
-    }
-
-    private static String generateMessage(String line, int lineNumber, Token token, String message) {
-        return "error reading style map at line " + lineNumber + ", character " + (token.getCharacterIndex() + 1) +
-            ": " + message + "\n\n" +
-            line + "\n" +
-            repeatString(" ", token.getCharacterIndex()) + "^";
-    }
-
-    private static String repeatString(String value, int times) {
-        StringBuilder builder = new StringBuilder();
-        for (int i = 0; i < times; i++) {
-            builder.append(value);
-        }
-        return builder.toString();
+    public ParseException(String message) {
+        super(message);
     }
 }
diff --git a/src/main/java/org/zwobble/mammoth/internal/styles/parsing/StyleMapParser.java b/src/main/java/org/zwobble/mammoth/internal/styles/parsing/StyleMapParser.java
index d1ceb72..8dd4099 100644
--- a/src/main/java/org/zwobble/mammoth/internal/styles/parsing/StyleMapParser.java
+++ b/src/main/java/org/zwobble/mammoth/internal/styles/parsing/StyleMapParser.java
@@ -22,7 +22,7 @@ public class StyleMapParser {
             try {
                 handleLine(styleMap, line);
             } catch (LineParseException exception) {
-                throw new ParseException(line, lineIndex + 1, exception.getToken(), exception.getMessage());
+                throw new ParseException(generateErrorMessage(line, lineIndex + 1, exception.getToken(), exception.getMessage()));
             }
         }
         return styleMap.build();
@@ -63,4 +63,19 @@ public class StyleMapParser {
             return HtmlPathParser.parse(tokens);
         }
     }
+
+    private static String generateErrorMessage(String line, int lineNumber, Token token, String message) {
+        return "error reading style map at line " + lineNumber + ", character " + (token.getCharacterIndex() + 1) +
+            ": " + message + "\n\n" +
+            line + "\n" +
+            repeatString(" ", token.getCharacterIndex()) + "^";
+    }
+
+    private static String repeatString(String value, int times) {
+        StringBuilder builder = new StringBuilder();
+        for (int i = 0; i < times; i += 1) {
+            builder.append(value);
+        }
+        return builder.toString();
+    }
 }