NRT Migration Phase 1

Directory.Build.props

@@ -28,5 +28,7 @@ See full changelog at https://github.com/sillsdev/liblcm/blob/develop/CHANGELOG.
     <UseFullSemVerForNuGet>false</UseFullSemVerForNuGet>
     <ChangelogFile>$(MSBuildThisFileDirectory)/CHANGELOG.md</ChangelogFile>
     <BuildInParallel>false</BuildInParallel>
+	<LangVersion>9.0</LangVersion>
+	<Nullable>warnings</Nullable>
   </PropertyGroup>
 </Project>

src/CSTools/Tools/Tools.csproj

@@ -16,5 +16,9 @@
     <PackageReference Include="GitVersion.MsBuild" Version="5.6.10" PrivateAssets="All" />
     <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.0.0" PrivateAssets="All" />
     <PackageReference Include="SIL.ReleaseTasks" Version="2.5.0" PrivateAssets="All" />
+    <PackageReference Include="Nullable" Version="1.3.1">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
   </ItemGroup>
 </Project>

src/CSTools/Tools/dfa.cs

@@ -602,7 +602,7 @@ public override int Match(string str, int pos, int max)
 			if (m_sub!=null)
 				a = m_sub.Match(str, pos, max);
 			if (m_alt!=null)
-				b = m_sub.Match(str, pos, max);
+				b = m_alt.Match(str, pos, max);
 			return (a>b)?a:b;
 		}
 		public override void Build(Nfa nfa)

src/CSTools/Tools/genbase.cs

@@ -8,6 +8,7 @@
 using System;
 using System.IO;
 using System.Text;
+using System.Diagnostics.CodeAnalysis;
 using YYClass;
 
 namespace SIL.LCModel.Tools
@@ -169,12 +170,8 @@ public void EmitClassDefin(string b,ref int p,int max,CsReader inf,string defbas
 			}
 			m_outFile.WriteLine("}");
 		}
-		/// <summary>
-		///
-		/// </summary>
-		/// <param name="n"></param>
-		/// <param name="p"></param>
-		/// <param name="str"></param>
+
+		[DoesNotReturn]
 		public void Error(int n,int p,string str)
 		{
 			Console.WriteLine(str);
@@ -185,6 +182,7 @@ public void Error(int n,int p,string str)
 			}
 			erh.Error(new CSToolsFatalException(n,line(p),position(p),"",str));
 		}
+
 		public virtual int line(int pos) { return 0; }
 		public virtual int position(int pos) { return pos; }
 		public virtual string Saypos(int pos) { return "at "+pos+": "; }

src/CSTools/Tools/lexer.cs

@@ -6,8 +6,10 @@
 using System.IO;
 using System.Text;
 using System.Globalization;
+using System.Diagnostics.CodeAnalysis;
 //using System.Runtime.Serialization.Formatters.Binary;
 
+
 namespace SIL.LCModel.Tools
 {
 
@@ -384,7 +386,7 @@ public static object create(string cls_name,Lexer yyl)
 				yyl.tokens.erh.Error(new CSToolsException(6,yyl,cls_name,String.Format("no factory for {0}",cls_name)));
 			try
 			{
-				return cr(yyl);
+				return cr!(yyl);
 			}
 			catch (CSToolsException x)
 			{
@@ -605,7 +607,7 @@ public static implicit operator int (SYMBOL s) // 4.0c
 				s = (SYMBOL)d;
 			try
 			{
-				rv =(int)d;
+				rv =(int)d!;
 			}
 			catch(Exception e)
 			{
@@ -638,8 +640,8 @@ public virtual bool Pass(Symbols syms,int snum,out ParserEntry entry)
 				string s = string.Format("No parsinginfo for symbol {0}",yyname());
 				syms.erh.Error(new CSToolsFatalException(9,yylx,yyname(),s));
 			}
-			bool r = pi.m_parsetable.Contains(snum);
-			entry = r?((ParserEntry)pi.m_parsetable[snum]):null;
+			bool r = pi != null && pi.m_parsetable.Contains(snum);
+			entry = pi != null && r ? ((ParserEntry)pi.m_parsetable[snum]) : null;
 			return r;
 		}
 		public virtual string yyname() { return "SYMBOL"; }
@@ -675,8 +677,8 @@ public override bool Pass(Symbols syms,int snum, out ParserEntry entry)
 			ParsingInfo pi = (ParsingInfo)syms.literalInfo[m_str];
 			if (pi==null)
 				syms.erh.Error(new CSToolsException(10,yylx,m_str,String.Format("Parser does not recognise literal <{0}>",m_str)));
-			bool r = pi.m_parsetable.Contains(snum);
-			entry = r?((ParserEntry)pi.m_parsetable[snum]):null;
+			bool r = pi != null && pi.m_parsetable.Contains(snum);
+			entry = pi != null && r ? ((ParserEntry)pi.m_parsetable[snum]) : null;
 			return r;
 		}
 		public override bool IsTerminal() { return true; }
@@ -971,20 +973,22 @@ public virtual void Error(Exception e)
 		{
 			counter++;
 			if (throwExceptions || (e is CSToolsFatalException))
-				throw(e);
-			if (e is CSToolsException)
+				throw e;
+			if (e is CSToolsException x)
 			{
-				CSToolsException x = (CSToolsException)e;
 				if (x.handled)
 					return;
 				x.handled = true;
-//				if (x.nLine !=0 || x.nChar!=0)
-//				{
-//					Console.WriteLine("line	"+x.nLine+", char "+x.nChar+": "+x.Message);
-//					return;
-//				}
+
 			}
 			Console.WriteLine(e.Message);
 		}
+
+		[DoesNotReturn]
+		public virtual void Error(CSToolsFatalException e)
+		{
+			counter++;
+			throw e;
+		}
 	}
 }

src/CSTools/Tools/parser.cs

@@ -1504,7 +1504,7 @@ protected bool Error(ref ParseStackEntry top, string str)
 								newtop = pe.m_action.Action(this); // before we change the stack
 							m_ungot = top.m_value;
 							Pop(ref top,((ParserReduce)pe).m_depth,er);
-							newtop.pos = top.m_value.pos;
+							newtop!.pos = top.m_value.pos;
 							top.m_value = newtop;
 						}
 						else
@@ -1554,6 +1554,8 @@ SYMBOL Parse()
 			ParseStackEntry top = new ParseStackEntry(this,0,NextSym());
 			for (;;)
 			{
+				if (top.m_value == null)
+					throw new NullReferenceException("Stack entry m_value cannot be null");
 				string cnm = top.m_value.yyname();
 				if (m_debug)
 				{
@@ -1693,7 +1695,8 @@ public static object create(string cls_name,Parser yyp)
 				yyp.m_symbols.erh.Error(new CSToolsException(16,yyp.m_lexer,"no factory for {"+cls_name+")"));
 			try
 			{
-				return cr(yyp);
+				if (cr != null)
+					return cr(yyp);
 			}
 			catch (CSToolsException e)
 			{

src/CSTools/pg/pg.cs

@@ -9,6 +9,7 @@
 using System.Collections;
 using System.IO;
 using System.Text;
+using System.Diagnostics.CodeAnalysis;
 using SIL.LCModel.Tools;
 
 public class PrecReference : TOKEN
@@ -782,7 +783,7 @@ internal void ParseProduction()
 			Error(39,m_tok.pos,string.Format("Illegal left hand side <{0}> for production",m_tok.yytext));
 		if (m_symbols.m_startSymbol==null)
 			m_symbols.m_startSymbol = lhs;
-		if (lhs.m_symtype==CSymbol.SymType.unknown)
+		if (lhs!.m_symtype==CSymbol.SymType.unknown)
 			lhs.m_symtype = CSymbol.SymType.nonterminal;
 		if ((!lhs.m_defined) && lhs.m_prods.Count==0)
 		{ // lhs not defined in %symbol statement and not previously a lhs

src/SIL.LCModel.Core/Phonology/PhonEnvRecognizer.cs

@@ -155,7 +155,7 @@ public bool Result
 		public static bool CanInsertItem(string sEnv, int ichEnd, int ichAnchor)
 		{
 			Debug.Assert(sEnv != null);
-			Debug.Assert(ichEnd <= sEnv.Length && ichAnchor <= sEnv.Length);
+			Debug.Assert(ichEnd <= sEnv!.Length && ichAnchor <= sEnv.Length);
 			if (ichEnd < 0 || ichAnchor < 0)
 				return false;
 			int ichSlash = sEnv.IndexOf('/');
@@ -199,7 +199,7 @@ public static bool CanInsertItem(string sEnv, int ichEnd, int ichAnchor)
 		public static bool CanInsertHashMark(string sEnv, int ichEnd, int ichAnchor)
 		{
 			Debug.Assert(sEnv != null);
-			Debug.Assert(ichEnd <= sEnv.Length && ichAnchor <= sEnv.Length);
+			Debug.Assert(ichEnd <= sEnv!.Length && ichAnchor <= sEnv.Length);
 			if (ichEnd < 0 || ichAnchor < 0)
 				return false;
 			int ichSlash = sEnv.IndexOf('/');
@@ -297,10 +297,10 @@ public static void CreateErrorMessageFromXml(string strRep1, string sXmlMessage,
 				// there were XML reserved characters in the environment.
 				// until we get that fixed, at least don't crash, just draw squiggly under the entire word
 				xdoc.LoadXml(sXmlMessage);
-				XmlAttribute posAttr = xdoc.DocumentElement.Attributes["pos"];
+				XmlAttribute posAttr = xdoc.DocumentElement!.Attributes["pos"];
 				pos = (posAttr != null) ? Convert.ToInt32(posAttr.Value) : 0;
 				XmlAttribute statusAttr = xdoc.DocumentElement.Attributes["status"];
-				sStatus = statusAttr.InnerText;
+				sStatus = statusAttr!.InnerText;
 			}
 			catch
 			{

src/SIL.LCModel.Core/SIL.LCModel.Core.csproj

@@ -25,6 +25,10 @@ SIL.LCModel.Core provides a base library with core functionality.</Description>
     <ProjectReference Include="..\CSTools\Tools\Tools.csproj" />
     <ProjectReference Include="..\SIL.LCModel.Build.Tasks\SIL.LCModel.Build.Tasks.csproj" />
     <ProjectReference Include="..\SIL.LCModel.Utils\SIL.LCModel.Utils.csproj" />
+    <PackageReference Include="Nullable" Version="1.3.1">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
   </ItemGroup>
 
   <ItemGroup>

src/SIL.LCModel.Core/Scripture/MultilingScrBooks.cs

@@ -464,9 +464,11 @@ public virtual string GetBookAbbrev(int nBook)
 
 			// No abbreviation found in primary writing system; get SIL code instead
 			wsNames = GetWsNames(kWsSilCodes); // SIL codes
-			Debug.Assert (wsNames != null);
+			if (wsNames == null)
+				throw new InvalidOperationException("Could not get SIL codes");
 			sAbbrev = wsNames.Name[nBook - 1]; // full SIL code is the .Name
-			Debug.Assert(sAbbrev != null);
+			if (sAbbrev == null)
+				throw new InvalidOperationException("Could not get abbreviation for book " + nBook);
 			return sAbbrev;
 		}
 

src/SIL.LCModel.Core/Text/CustomIcu.cs

@@ -178,9 +178,10 @@ public static void InitIcuDataDir()
 			// application (e.g. Flex & Paratext)
 			if (Platform.IsWindows)
 			{
-				var executingAssemblyFolder = Uri.UnescapeDataString(new UriBuilder(Assembly.GetExecutingAssembly().CodeBase).Path);
+				var executingAssemblyFolder = Uri.UnescapeDataString(new UriBuilder(Assembly.GetExecutingAssembly().Location).Path);
 				var assemblyDir = Path.GetDirectoryName(executingAssemblyFolder);
-				// ReSharper disable once AssignNullToNotNullAttribute -- The directory of the executing assembly will not be null
+				if (assemblyDir == null)
+					throw new InvalidOperationException("Could not get assembly directory from " + executingAssemblyFolder);
 				var icu32Path = Path.Combine(assemblyDir, "lib", "win-x86");
 				var icu64Path = Path.Combine(assemblyDir, "lib", "win-x64");
 				var flexIcu32Path = Path.Combine(assemblyDir, "lib", "x86");

src/SIL.LCModel.Core/Text/PUACharacter.cs

@@ -1018,12 +1018,11 @@ protected int CompareRegions(string property2)
 		public override int CompareTo(object obj)
 		{
 			// if they give us a UCDCharacter, compare Properties
-			if (obj is UCDCharacter)
+			if (obj is UCDCharacter c)
 			{
-				UCDCharacter ucdChar = obj as UCDCharacter;
-				if (SameRegion(ucdChar))
-					return MiscUtils.CompareHex(CodePoint, ucdChar.CodePoint);
-				return CompareRegions(ucdChar.Property);
+				if (SameRegion(c))
+					return MiscUtils.CompareHex(CodePoint, c.CodePoint);
+				return CompareRegions(c.Property);
 			}
 				// if they give us a string, assume its a codepoint
 			else if (obj is string)

src/SIL.LCModel.Core/Text/TsString.cs

@@ -459,7 +459,7 @@ private ITsString get_NormalizedFormAndFixOffsets(FwNormalizationMode nm, ArrayP
 							// Note that our local mapping is from the start of this segment, but we want to keep track of indexes from the start
 							// of the *string*. (Both the original string and the output, normalized string). So we adjust the indexes here.
 							if (mapping.isFirstCharOfDecomposition)
-								stringOffsetMapping[segmentMin + mapping.origIdx] = outputLenSoFar + mapping.normIdx;
+								stringOffsetMapping![segmentMin + mapping.origIdx] = outputLenSoFar + mapping.normIdx;
 						}
 					}
 				}
@@ -489,7 +489,7 @@ private ITsString get_NormalizedFormAndFixOffsets(FwNormalizationMode nm, ArrayP
 							resultBuilder.SetProperties(outputIdx, outputIdx + size, origProperties);
 							// And if we also need to fix up offsets at the end, we keep track of the ones we'll need
 							if (willFixOffsets && mapping.isFirstCharOfDecomposition)
-								stringOffsetMapping[segmentMin + mapping.origIdx] = outputLenSoFar + mapping.normIdx;
+								stringOffsetMapping![segmentMin + mapping.origIdx] = outputLenSoFar + mapping.normIdx;
 						}
 					}
 
@@ -526,11 +526,11 @@ private ITsString get_NormalizedFormAndFixOffsets(FwNormalizationMode nm, ArrayP
 			}
 			if (willFixOffsets)
 			{
-				stringOffsetMapping[segmentMin] = resultBuilder.Length;
+				stringOffsetMapping![segmentMin] = resultBuilder.Length;
 				int ptrSize = Marshal.SizeOf(typeof(IntPtr));
 				for (int i = 0; i < numOffsetsToFix; i++)
 				{
-					IntPtr offsetPtr = Marshal.ReadIntPtr(oldOffsetsToFix.IntPtr, i * ptrSize);
+					IntPtr offsetPtr = Marshal.ReadIntPtr(oldOffsetsToFix!.IntPtr, i * ptrSize);
 					int oldOffset = Marshal.ReadInt32(offsetPtr);
 					int newOffset;
 					if (stringOffsetMapping.TryGetValue(oldOffset, out newOffset))

src/SIL.LCModel.Core/Text/TsStringUtils.cs

@@ -1387,12 +1387,13 @@ public static ITsString MergeString(ITsString source, ITsString dest)
 		/// ------------------------------------------------------------------------------------
 		public static ITsString MergeString(ITsString source, ITsString dest, bool fConcatenateIfBoth)
 		{
-			string destText = (dest != null) ? dest.Text : null;
-			string sourceText = (source != null) ? source.Text : null;
-
-			if (string.IsNullOrEmpty(destText) && !string.IsNullOrEmpty(sourceText))
+			if (dest == null && source == null)
+				return null;
+			if (dest == null || string.IsNullOrEmpty(dest.Text))
 				return source;
-			else if (fConcatenateIfBoth && !string.IsNullOrEmpty(destText) && !string.IsNullOrEmpty(sourceText) && !dest.Equals(source))
+			if (source == null || string.IsNullOrEmpty(source.Text))
+				return dest;
+			if (fConcatenateIfBoth && !dest.Equals(source))
 			{
 				// concatenate
 				ITsStrBldr tsb = dest.GetBldr();
@@ -1633,23 +1634,23 @@ public static ITsTextProps PropsForWs(int ws)
 			Justification = "If a tss is null, crunBoth will be 0, so we'll never try to access it.")]
 		public static TsStringDiffInfo GetDiffsInTsStrings(ITsString tssOld, ITsString tssNew)
 		{
+			if (tssOld == null && tssNew == null)
+				return null;
+			if (tssOld == null)
+				return new TsStringDiffInfo(0, tssNew.Length, 0, true);
+			if (tssNew == null)
+				return new TsStringDiffInfo(0, 0, tssOld.Length, true);
 			// no diff found
 			var ichMin = -1;
 
 			int cchOld = 0;
 			int crunOld = 0;
 			int crunNew = 0;
 			int cchNew = 0;
-			if (tssNew != null)
-			{
-				cchNew = tssNew.Length;
-				crunNew = tssNew.RunCount;
-			}
-			if (tssOld != null)
-			{
-				cchOld = tssOld.Length;
-				crunOld = tssOld.RunCount;
-			}
+			cchNew = tssNew.Length;
+			crunNew = tssNew.RunCount;
+			cchOld = tssOld.Length;
+			crunOld = tssOld.RunCount;
 			var crunBoth = Math.Min(crunOld, crunNew);
 
 			// Set ichMin to the index of the first character that is different or has different properties.

src/SIL.LCModel.Core/WritingSystems/CoreWritingSystemDefinition.cs

@@ -67,12 +67,16 @@ private void MainCharacterSetChanged(object sender, NotifyCollectionChangedEvent
 			switch (e.Action)
 			{
 				case NotifyCollectionChangedAction.Add:
+					if (e.NewItems == null) throw new NullReferenceException("e.NewItems");
 					AddWordFormingOverrides(e.NewItems.Cast<string>());
 					break;
 				case NotifyCollectionChangedAction.Remove:
+					if (e.OldItems == null) throw new NullReferenceException("e.OldItems");
 					RemoveWordFormingOverrides(e.OldItems.Cast<string>());
 					break;
 				case NotifyCollectionChangedAction.Replace:
+					if (e.NewItems == null) throw new NullReferenceException("e.NewItems");
+					if (e.OldItems == null) throw new NullReferenceException("e.OldItems");
 					RemoveWordFormingOverrides(e.OldItems.Cast<string>());
 					AddWordFormingOverrides(e.NewItems.Cast<string>());
 					break;

src/SIL.LCModel.Core/WritingSystems/ValidCharacters.cs

@@ -596,7 +596,8 @@ public static IEnumerable<string> ParseLegacyWordFormingCharOverrides(string pat
 				{
 					foreach (XmlNode charNode in charsList)
 					{
-						string codepointStr = charNode.Attributes["val"].InnerText;
+						string codepointStr = charNode.Attributes?["val"]?.InnerText;
+						if (codepointStr == null) throw new InvalidOperationException("Could not get codepoint from " + charNode.OuterXml);
 						int codepoint = Convert.ToInt32(codepointStr, 16);
 						var c = (char) codepoint;
 						result.Add(c.ToString(CultureInfo.InvariantCulture));

src/SIL.LCModel.Utils/FileUtils.cs

@@ -441,6 +441,8 @@ public static string ActualFilePath(string sPathname)
 				return sPathname.Normalize(NormalizationForm.FormD);
 
 			string sDir = Path.GetDirectoryName(sPathname);
+			if (sDir == null)
+				throw new InvalidOperationException("Could not get directory name from path " + sPathname);
 			string sFile = Path.GetFileName(sPathname).Normalize();
 			if (!Platform.IsUnix) // Using IsUnix to decide if a file system is case sensitive
 			{					// isn't the best way since some Unix file systems are case