Various fixes/improvements.

Fluent.Net.SimpleExample/TranslationService.cs

@@ -72,19 +72,6 @@ public string GetString(string id, IDictionary<string, object> args = null,
             return "";
         }
 
-        public string PreferredLocale => _contexts.First().Locales.First();
-
-        CultureInfo _culture;
-        public CultureInfo Culture
-        {
-            get
-            {
-                if (_culture == null)
-                {
-                    _culture = new CultureInfo(PreferredLocale);
-                }
-                return _culture;
-            }
-        }
+        public CultureInfo Culture => _contexts.First().Culture;
     }
 }

Fluent.Net.Test/IsolatingTest.cs

@@ -67,7 +67,7 @@ public void IsolatesInterpolatedDateTypedVariables()
             var args = new Dictionary<string, object> { { "arg", dt } };
             var msg = ctx.GetMessage("baz");
             var val = ctx.Format(msg, args, errors);
-            var dtf = dt.ToString(new CultureInfo(ctx.Locales.First()));
+            var dtf = dt.ToString(ctx.Culture);
             val.Should().Be($"{FSI}{dtf}{PDI} Baz");
             errors.Count.Should().Be(0);
         }

Fluent.Net.Test/MessageContextTest.cs

@@ -2,6 +2,7 @@
 using NUnit.Framework;
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 
 namespace Fluent.Net.Test
 {
@@ -203,7 +204,7 @@ public void TestFluentNumber()
         public void TestFluentDateTime()
         {
             var dt = new FluentDateTime(new DateTime(2009, 01, 02));
-            var ctx = new MessageContext("en-US");
+            var ctx = new MessageContext(new CultureInfo("en-US", useUserOverride: false));
             dt.Format(ctx).Should().Be("1/2/2009 12:00:00 AM");
             dt.Match(ctx, new FluentDateTime(new DateTime(2009, 01, 02))).Should().BeTrue();
             dt.Match(ctx, new FluentDateTime(new DateTime(2009, 01, 03))).Should().BeFalse();

Fluent.Net.Test/MessageContextTestBase.cs

@@ -1,14 +1,14 @@
 using FluentAssertions;
 using System.Collections.Generic;
+using System.Globalization;
 
 namespace Fluent.Net.Test
 {
     public class MessageContextTestBase : FtlTestBase
     {
         protected static MessageContext CreateContext(string ftl, bool useIsolating = false)
         {
-            var locales = new string[] { "en-US", "en" };
-            var ctx = new MessageContext(locales, new MessageContextOptions()
+            var ctx = new MessageContext(new CultureInfo("en-US", useUserOverride: false), new MessageContextOptions()
                 { UseIsolating = useIsolating });
             var errors = ctx.AddMessages(Ftl(ftl));
             errors.Should().BeEquivalentTo(new List<ParseException>());

Fluent.Net.Test/Plural/LocaleRulesTest.cs

@@ -7,41 +7,35 @@ namespace Fluent.Net.Test.Plural
     public class LocaleRulesTest
     {
         [Test]
-        public void CheckEnRules()
+        [TestCase("en", "1", ExpectedResult = "one")]
+        [TestCase("en-US", "1", ExpectedResult = "one")]
+        [TestCase("en", "1.6", ExpectedResult = "other")]
+        [TestCase("en", "1.0", ExpectedResult = "other")]
+        [TestCase("en", "9", ExpectedResult = "other")]
+        // for lt:
+        // <pluralRule count="one">n % 10 = 1 and n % 100 != 11..19 @integer 1, 21, 31, 41, 51, 61, 71, 81, 101, 1001, … @decimal 1.0, 21.0, 31.0, 41.0, 51.0, 61.0, 71.0, 81.0, 101.0, 1001.0, …</pluralRule>
+        // <pluralRule count="few">n % 10 = 2..9 and n % 100 != 11..19 @integer 2~9, 22~29, 102, 1002, … @decimal 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 22.0, 102.0, 1002.0, …</pluralRule>
+        // <pluralRule count="many">f != 0   @decimal 0.1~0.9, 1.1~1.7, 10.1, 100.1, 1000.1, …</pluralRule>
+        // <pluralRule count="other"> @integer 0, 10~20, 30, 40, 50, 60, 100, 1000, 10000, 100000, 1000000, … @decimal 0.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 100.0, 1000.0, 10000.0, 100000.0, 1000000.0, …</pluralRule>
+        [TestCase("lt", "1", ExpectedResult = "one")]
+        [TestCase("lt", "11", ExpectedResult = "other")]
+        [TestCase("lt", "21", ExpectedResult = "one")]
+        [TestCase("lt", "91", ExpectedResult = "one")]
+        [TestCase("lt", "101", ExpectedResult = "one")]
+        [TestCase("lt", "2", ExpectedResult = "few")]
+        [TestCase("lt", "37", ExpectedResult = "few")]
+        [TestCase("lt", "9", ExpectedResult = "few")]
+        [TestCase("lt", "10", ExpectedResult = "other")]
+        [TestCase("lt", "23", ExpectedResult = "few")]
+        [TestCase("lt", "0.6", ExpectedResult = "many")]
+        [TestCase("lt", "1.1", ExpectedResult = "many")]
+        [TestCase("lt", "2.0", ExpectedResult = "few")]
+        [TestCase("lt", "1234.456", ExpectedResult = "many")]
+        [TestCase("lt", "14", ExpectedResult = "other")]
+        [TestCase("lt", "40", ExpectedResult = "other")]
+        public string TestPluralSelect(string locale, string num)
         {
-            LocaleRules.Select("en", "1").Should().Be("one");
-            LocaleRules.Select("en", "1.6").Should().Be("other");
-            LocaleRules.Select("en", "1.0").Should().Be("other");
-            LocaleRules.Select("en", "9").Should().Be("other");
-        }
-
-        [Test]
-        public void CheckLtRules()
-        {
-            // <pluralRule count="one">n % 10 = 1 and n % 100 != 11..19 @integer 1, 21, 31, 41, 51, 61, 71, 81, 101, 1001, … @decimal 1.0, 21.0, 31.0, 41.0, 51.0, 61.0, 71.0, 81.0, 101.0, 1001.0, …</pluralRule>
-            // <pluralRule count="few">n % 10 = 2..9 and n % 100 != 11..19 @integer 2~9, 22~29, 102, 1002, … @decimal 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 22.0, 102.0, 1002.0, …</pluralRule>
-            // <pluralRule count="many">f != 0   @decimal 0.1~0.9, 1.1~1.7, 10.1, 100.1, 1000.1, …</pluralRule>
-            // <pluralRule count="other"> @integer 0, 10~20, 30, 40, 50, 60, 100, 1000, 10000, 100000, 1000000, … @decimal 0.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 100.0, 1000.0, 10000.0, 100000.0, 1000000.0, …</pluralRule>
-
-            LocaleRules.Select("lt", "1").Should().Be("one");
-            LocaleRules.Select("lt", "11").Should().Be("other");
-            LocaleRules.Select("lt", "21").Should().Be("one");
-            LocaleRules.Select("lt", "91").Should().Be("one");
-            LocaleRules.Select("lt", "101").Should().Be("one");
-
-            LocaleRules.Select("lt", "2").Should().Be("few");
-            LocaleRules.Select("lt", "37").Should().Be("few");
-            LocaleRules.Select("lt", "9").Should().Be("few");
-            LocaleRules.Select("lt", "10").Should().Be("other");
-            LocaleRules.Select("lt", "23").Should().Be("few");
-
-            LocaleRules.Select("lt", "0.6").Should().Be("many");
-            LocaleRules.Select("lt", "1.1").Should().Be("many");
-            LocaleRules.Select("lt", "2.0").Should().Be("few");
-            LocaleRules.Select("lt", "1234.456").Should().Be("many");
-
-            LocaleRules.Select("lt", "14").Should().Be("other");
-            LocaleRules.Select("lt", "40").Should().Be("other");
+            return LocaleRules.Select(locale, num);
         }
     }
 }

Fluent.Net/BuiltIns.cs

@@ -0,0 +1,35 @@
+using System;
+using System.Collections.Generic;
+
+namespace Fluent.Net
+{
+    internal static class BuiltIns
+    {
+        public static FluentType Number(IList<object> args, IDictionary<string, object> options)
+        {
+            // TODO: add to errors?  what we doin here?
+            if (args.Count != 1)
+            {
+                throw new Exception("Too many arguments to NUMBER() function");
+            }
+            if (args[0].GetType() != typeof(FluentNumber))
+            {
+                throw new Exception("NUMBER() expected an argument of type FluentNumber");
+            }
+            return (FluentNumber)args[0];
+        }
+
+        public static FluentType DateTime(IList<object> args, IDictionary<string, object> options)
+        {
+            if (args.Count != 1)
+            {
+                throw new Exception("Too many arguments to DATETIME() function");
+            }
+            if (args[0].GetType() != typeof(FluentDateTime))
+            {
+                throw new Exception("DATETIME() expected an argument of type FluentDateTime");
+            }
+            return (FluentDateTime)args[0];
+        }
+    }
+}

Fluent.Net/FluentError.cs

@@ -0,0 +1,36 @@
+namespace Fluent.Net
+{
+    public abstract class FluentError
+    {
+        public string Message { get; set; }
+
+        public FluentError(string message)
+        {
+            Message = message;
+        }
+    }
+
+    class RangeError : FluentError
+    {
+        public RangeError(string message) :
+            base(message)
+        {
+        }
+    }
+
+    class TypeError : FluentError
+    {
+        public TypeError(string message) :
+            base(message)
+        {
+        }
+    }
+
+    class ReferenceError : FluentError
+    {
+        public ReferenceError(string message) :
+            base(message)
+        {
+        }
+    }
+}

Fluent.Net/FluentResource.cs

@@ -0,0 +1,30 @@
+using System.Collections.Generic;
+using System.IO;
+using Fluent.Net.RuntimeAst;
+
+namespace Fluent.Net
+{
+    /// <summary>
+    /// Fluent Resource is a structure storing a map
+    /// of localization entries.
+    /// </summary>
+    public class FluentResource
+    {
+        public IDictionary<string, Message> Entries { get; }
+        public IList<ParseException> Errors { get; }
+
+        public FluentResource(IDictionary<string, Message> entries,
+            IList<ParseException> errors)
+        {
+            Entries = entries;
+            Errors = errors;
+        }
+
+        public static FluentResource FromReader(TextReader reader)
+        {
+            var parser = new RuntimeParser();
+            var resource = parser.GetResource(reader);
+            return new FluentResource(resource.Entries, resource.Errors);
+        }
+    }
+}