feat: Support custom templates for commits + PRs

This commit introduces mustache templates for commit messages, and pull
request titles and bodies.

The design consists of templates with predefined properties. A custom
template can be provided.

Stubble has been chosen as the template renderer.

It is possible to define additional context for the templates, this also
includes delegates. These can be provided as the value of a "_delegates"
key in the context.

NuKeeper.Abstractions.Tests/Configuration/FileSettingsReaderTests.cs

@@ -5,6 +5,7 @@
 using NuKeeper.Abstractions.Output;
 using NUnit.Framework;
 using System;
+using System.Collections.Generic;
 using System.Globalization;
 using System.IO;
 
@@ -60,6 +61,8 @@ public void MissingFileReturnsNoSettings()
             Assert.That(data.Platform, Is.Null);
             Assert.That(data.BranchNameTemplate, Is.Null);
             Assert.That(data.DeleteBranchAfterMerge, Is.Null);
+            Assert.That(data.CommitMessageTemplate, Is.Null);
+            Assert.That(data.Context, Is.Null);
         }
 
         [Test]
@@ -92,6 +95,8 @@ public void EmptyConfigReturnsNoSettings()
             Assert.That(data.Platform, Is.Null);
             Assert.That(data.BranchNameTemplate, Is.Null);
             Assert.That(data.DeleteBranchAfterMerge, Is.Null);
+            Assert.That(data.CommitMessageTemplate, Is.Null);
+            Assert.That(data.Context, Is.Null);
         }
 
         private const string FullFileData = @"{
@@ -116,7 +121,9 @@ public void EmptyConfigReturnsNoSettings()
                ""OutputFileName"" : ""out_42.txt"",
                ""LogDestination"" : ""file"",
                ""Platform"" : ""Bitbucket"",
-               ""DeleteBranchAfterMerge"": ""true""
+               ""DeleteBranchAfterMerge"": ""true"",
+               ""CommitMessageTemplate"": ""📦 Automatic update from {{packageName}} to {{packageVersion}}"",
+               ""Context"": { ""company"": ""NuKeeper"", ""issue"": ""JIRA-001"" }
         }";
 
         [Test]
@@ -139,6 +146,17 @@ public void PopulatedConfigReturnsAllStringSettings()
             Assert.That(data.OutputFileName, Is.EqualTo("out_42.txt"));
             Assert.That(data.BranchNameTemplate, Is.EqualTo("nukeeper/MyBranch"));
             Assert.That(data.DeleteBranchAfterMerge, Is.EqualTo(true));
+            Assert.That(data.CommitMessageTemplate, Is.EqualTo("📦 Automatic update from {{packageName}} to {{packageVersion}}"));
+            Assert.That(
+                data.Context,
+                Is.EquivalentTo(
+                    new Dictionary<string, object>
+                    {
+                        { "company", "NuKeeper" },
+                        { "issue", "JIRA-001" }
+                    }
+                )
+            );
         }
 
         [Test]
@@ -206,7 +224,9 @@ public void ConfigKeysAreCaseInsensitive()
                ""vErBoSiTy"": ""Q"",
                ""CHANGE"": ""PATCH"",
                ""bRanCHNamETempLATe"": ""nukeeper/MyBranch"",
-               ""deLeTEBranCHafTERMerge"": ""true""
+               ""deLeTEBranCHafTERMerge"": ""true"",
+               ""coMmItmESsageTeMpLate"": ""📦 Automatic update from {{packageName}} to {{packageVersion}}"",
+               ""cOntExT"": { ""company"": ""NuKeeper"", ""issue"": ""JIRA-001"" }
             }";
 
             var path = MakeTestFile(configData);
@@ -230,6 +250,17 @@ public void ConfigKeysAreCaseInsensitive()
             Assert.That(data.Change, Is.EqualTo(VersionChange.Patch));
             Assert.That(data.BranchNameTemplate, Is.EqualTo("nukeeper/MyBranch"));
             Assert.That(data.DeleteBranchAfterMerge, Is.EqualTo(true));
+            Assert.That(data.CommitMessageTemplate, Is.EqualTo("📦 Automatic update from {{packageName}} to {{packageVersion}}"));
+            Assert.That(
+                data.Context,
+                Is.EquivalentTo(
+                    new Dictionary<string, string>
+                    {
+                        { "company", "NuKeeper" },
+                        { "issue", "JIRA-001" }
+                    }
+                )
+            );
         }
 
         [Test]

NuKeeper.Abstractions/CollaborationModels/CommitUpdateMessageTemplate.cs

@@ -0,0 +1,47 @@
+using NuKeeper.Abstractions.CollaborationPlatform;
+
+namespace NuKeeper.Abstractions.CollaborationModels
+{
+    public class CommitUpdateMessageTemplate : UpdateMessageTemplate
+    {
+        private const string CommitEmoji = "📦";
+
+        public CommitUpdateMessageTemplate()
+            : base(new StubbleTemplateRenderer())
+        {
+            PackageEmoji = CommitEmoji;
+        }
+
+        public static string DefaultTemplate { get; } =
+            "{{#packageEmoji}}{{packageEmoji}} {{/packageEmoji}}Automatic update of {{^multipleChanges}}{{#packages}}{{Name}} to {{Version}}{{/packages}}{{/multipleChanges}}{{#multipleChanges}}{{packageCount}} packages{{/multipleChanges}}";
+
+        public override string Value
+        {
+            get
+            {
+                return CustomTemplate ?? DefaultTemplate;
+            }
+        }
+
+        public string CustomTemplate { get; set; }
+
+        public object PackageEmoji
+        {
+            get
+            {
+                Context.TryGetValue(Constants.Template.PackageEmoji, out var packageEmoji);
+                return packageEmoji;
+            }
+            set
+            {
+                Context[Constants.Template.PackageEmoji] = value;
+            }
+        }
+
+        public override void Clear()
+        {
+            base.Clear();
+            PackageEmoji = CommitEmoji;
+        }
+    }
+}

NuKeeper.Abstractions/CollaborationModels/DefaultPullRequestBodyTemplate.cs

@@ -0,0 +1,45 @@
+using NuKeeper.Abstractions.CollaborationPlatform;
+
+namespace NuKeeper.Abstractions.CollaborationModels
+{
+    public class DefaultPullRequestBodyTemplate : UpdateMessageTemplate
+    {
+        public DefaultPullRequestBodyTemplate()
+            : base(new StubbleTemplateRenderer()) { }
+
+        public static string DefaultTemplate { get; } =
+@"{{#multipleChanges}}{{packageCount}} packages were updated in {{projectsUpdated}} project{{#multipleProjects}}s{{/multipleProjects}}:
+{{#packages}}`{{Name}}`{{^Last}}, {{/Last}}{{/packages}}
+<details>
+<summary>Details of updated packages</summary>
+
+{{/multipleChanges}}
+{{#packages}}NuKeeper has generated a {{ActualChange}} update of `{{Name}}` to `{{Version}}`{{^MultipleUpdates}} from `{{FromVersion}}`{{/MultipleUpdates}}
+{{#MultipleUpdates}}{{ProjectsUpdated}} versions of `{{Name}}` were found in use: {{#Updates}}`{{FromVersion}}`{{^Last}}, {{/Last}}{{/Updates}}{{/MultipleUpdates}}
+{{#Publication}}`{{Name}} {{Version}}` was published at `{{Date}}`, {{Ago}}{{/Publication}}
+{{#LatestVersion}}There is also a higher version, `{{Name}} {{Version}}`{{#Publication}} published at `{{Date}}`, {{Ago}}{{/Publication}}, but this was not applied as only `{{AllowedChange}}` version changes are allowed.
+{{/LatestVersion}}
+{{ProjectsUpdated}} project update{{#MultipleProjectsUpdated}}s{{/MultipleProjectsUpdated}}:
+{{#Updates}}
+Updated `{{SourceFilePath}}` to `{{Name}}` `{{ToVersion}}` from `{{FromVersion}}`
+{{/Updates}}
+{{#IsFromNuget}}
+
+[{{Name}} {{Version}} on NuGet.org]({{Url}})
+{{/IsFromNuget}}
+{{/packages}}
+{{#multipleChanges}}
+</details>
+
+{{/multipleChanges}}
+{{#footer}}
+{{WarningMessage}}
+**NuKeeper**: {{NuKeeperUrl}}
+{{/footer}}
+";
+
+        public string CustomTemplate { get; set; }
+
+        public override string Value => CustomTemplate ?? DefaultTemplate;
+    }
+}

NuKeeper.Abstractions/CollaborationModels/DefaultPullRequestTitleTemplate.cs

@@ -0,0 +1,17 @@
+using NuKeeper.Abstractions.CollaborationPlatform;
+
+namespace NuKeeper.Abstractions.CollaborationModels
+{
+    public class DefaultPullRequestTitleTemplate : UpdateMessageTemplate
+    {
+        public DefaultPullRequestTitleTemplate()
+            : base(new StubbleTemplateRenderer()) { }
+
+        public static string DefaultTemplate { get; } =
+            "Automatic update of {{^multipleChanges}}{{#packages}}{{Name}} to {{Version}}{{/packages}}{{/multipleChanges}}{{#multipleChanges}}{{packageCount}} packages{{/multipleChanges}}";
+
+        public string CustomTemplate { get; set; }
+
+        public override string Value => CustomTemplate ?? DefaultTemplate;
+    }
+}

NuKeeper.Abstractions/CollaborationModels/FooterTemplate.cs

@@ -0,0 +1,10 @@
+namespace NuKeeper.Abstractions.CollaborationModels
+{
+    public class FooterTemplate
+    {
+#pragma warning disable CA1056 // Uri properties should not be strings
+        public string NuKeeperUrl { get; set; }
+#pragma warning restore CA1056 // Uri properties should not be strings
+        public string WarningMessage { get; set; }
+    }
+}

NuKeeper.Abstractions/CollaborationModels/LatestPackageTemplate.cs

@@ -0,0 +1,11 @@
+namespace NuKeeper.Abstractions.CollaborationModels
+{
+    public class LatestPackageTemplate
+    {
+        public string Version { get; set; }
+#pragma warning disable CA1056 // Uri properties should not be strings
+        public string Url { get; set; }
+#pragma warning restore CA1056 // Uri properties should not be strings
+        public PublicationTemplate Publication { get; set; }
+    }
+}

NuKeeper.Abstractions/CollaborationModels/PackageTemplate.cs

@@ -0,0 +1,32 @@
+#pragma warning disable CA1819 // Properties should not return arrays
+#pragma warning disable CA1056 // Uri properties should not be strings
+
+using System;
+using System.Linq;
+
+namespace NuKeeper.Abstractions.CollaborationModels
+{
+    public class PackageTemplate
+    {
+        public string Name { get; set; }
+        public string Version { get; set; }
+        public string FromVersion => MultipleUpdates ?
+            string.Empty
+            : Updates.FirstOrDefault()?.FromVersion;
+        public string AllowedChange { get; set; }
+        public string ActualChange { get; set; }
+        public PublicationTemplate Publication { get; set; }
+        public int ProjectsUpdated =>
+            Updates?.Length ?? 0;
+        public LatestPackageTemplate LatestVersion { get; set; }
+        public string Url { get; set; }
+        public string SourceUrl { get; set; }
+        public bool IsFromNuget { get; set; }
+        public UpdateTemplate[] Updates { get; set; }
+        public bool MultipleProjectsUpdated => Updates?.Length > 1;
+        public bool MultipleUpdates => Updates?
+            .Select(u => u.FromVersion)
+            .Distinct(StringComparer.InvariantCultureIgnoreCase)
+            .Count() > 1;
+    }
+}

NuKeeper.Abstractions/CollaborationModels/PublicationTemplate.cs

@@ -0,0 +1,8 @@
+namespace NuKeeper.Abstractions.CollaborationModels
+{
+    public class PublicationTemplate
+    {
+        public string Date { get; set; }
+        public string Ago { get; set; }
+    }
+}