azp: vscode extension completions (#403)

* semantic highlighting
* fix schema of task step to include target

src/Sdk/Actions/ActionsDescriptions.cs

@@ -0,0 +1,38 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Reflection;
+
+using Newtonsoft.Json;
+
+namespace Sdk.Actions {
+
+    public class ActionsDescriptions
+    {
+
+        public static Dictionary<string, TSource> ToOrdinalIgnoreCaseDictionary<TSource>(IEnumerable<KeyValuePair<string, TSource>> source) {
+            var ret = new Dictionary<string, TSource>(StringComparer.OrdinalIgnoreCase);
+            foreach(var kv in source) {
+                ret[kv.Key] = kv.Value;
+            }
+            return ret;
+        }
+
+        public string Description { get; set; }
+
+        public Dictionary<string, string> Versions { get; set; }
+        public static Dictionary<string, Dictionary<string, ActionsDescriptions>> LoadDescriptions() {
+            var assembly = Assembly.GetExecutingAssembly();
+            var json = default(String);
+            using (var stream = assembly.GetManifestResourceStream("descriptions.json"))
+            using (var streamReader = new StreamReader(stream))
+            {
+                json = streamReader.ReadToEnd();
+            }
+
+            return ToOrdinalIgnoreCaseDictionary(JsonConvert.DeserializeObject<Dictionary<string, Dictionary<string, ActionsDescriptions>>>(json).Select(kv => new KeyValuePair<string, Dictionary<string, ActionsDescriptions>>(kv.Key, ToOrdinalIgnoreCaseDictionary(kv.Value))));
+        }
+    }
+
+}

src/Sdk/AzurePipelines/CompletionItem.cs

@@ -0,0 +1,62 @@
+using System.Reflection.Emit;
+
+using Newtonsoft.Json;
+using Newtonsoft.Json.Serialization;
+
+namespace Runner.Server.Azure.Devops {
+
+    [JsonObject("", NamingStrategyType = typeof(CamelCaseNamingStrategy), ItemNullValueHandling = NullValueHandling.Ignore)]
+    public class CompletionItemLabel {
+        public string Label { get; set; }
+        public string Description { get; set; }
+        public string Detail { get; set; }
+    }
+    [JsonObject("", NamingStrategyType = typeof(CamelCaseNamingStrategy), ItemNullValueHandling = NullValueHandling.Ignore)]
+    public class MarkdownString {
+        public string Value { get; set; }
+        public bool? SupportThemeIcons { get; set; }
+        public bool? SupportHtml { get; set; }
+    }
+
+    [JsonObject("", NamingStrategyType = typeof(CamelCaseNamingStrategy), ItemNullValueHandling = NullValueHandling.Ignore)]
+    public class SnippedString {
+        public string Value { get; set; }
+    }
+
+    [JsonObject("", NamingStrategyType = typeof(CamelCaseNamingStrategy), ItemNullValueHandling = NullValueHandling.Ignore)]
+    public class Position {
+        public long Character { get; set; }
+        public long Line { get; set; }
+    }
+
+    [JsonObject("", NamingStrategyType = typeof(CamelCaseNamingStrategy), ItemNullValueHandling = NullValueHandling.Ignore)]
+    public class Range {
+        public Position Start { get; set; }
+        public Position End { get; set; }
+        public bool? IsEmpty { get; set; }
+        public bool? IsSingleLine { get; set; }
+    }
+    [JsonObject("", NamingStrategyType = typeof(CamelCaseNamingStrategy), ItemNullValueHandling = NullValueHandling.Ignore)]
+    public class InsertReplaceRange {
+        public Range Inserting { get; set; }
+        public Range Replacing { get; set; }
+    }
+
+    [JsonObject("", NamingStrategyType = typeof(CamelCaseNamingStrategy), ItemNullValueHandling = NullValueHandling.Ignore)]
+    public class CompletionItem {
+        public CompletionItemLabel Label { get; set; }
+        public string FilterText { get; set; }
+        public SnippedString InsertText { get; set; }
+        public string SortText { get; set; }
+        public bool? Preselect { get; set; }
+        public string Detail { get; set; }
+        public string[] CommitCharacters { get; set; }
+        public bool? KeepWhitespace { get; set; }
+        public int? Kind { get; set; }
+        public InsertReplaceRange Range { get; set; }
+        public MarkdownString Documentation { get; set; }
+
+        [JsonIgnore]
+        public int Priority { get; set; } = 0;
+    }
+}

src/Sdk/AzurePipelines/Context.cs

@@ -1,4 +1,5 @@
 using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.ObjectTemplating;
 using GitHub.DistributedTask.ObjectTemplating.Tokens;
 using System;
 using System.Collections.Generic;
@@ -17,6 +18,10 @@ public class Context {
         public ITaskByNameAndVersionProvider TaskByNameAndVersion { get; set; }
         public IRequiredParametersProvider RequiredParametersProvider { get; set; }
         public List<string> FileTable { get; set; } = new List<string>();
+        public int Column { get; internal set; }
+        public int Row { get; internal set; }
+        internal List<AutoCompleteEntry> AutoCompleteMatches { get; set; }
+        public List<int> SemTokens { get; internal set; }
 
         public Context Clone() {
             return MemberwiseClone() as Context;
@@ -28,6 +33,9 @@ public Context ChildContext(MappingToken template, string path = null) {
             }
             var childContext = Clone();
             childContext.RequiredParametersProvider = null;
+            childContext.AutoCompleteMatches = null;
+            childContext.Column = 0;
+            childContext.Row = 0;
             foreach(var kv in template) {
                 switch(kv.Key.AssertString("key").Value) {
                     case "resources":