add generic AppendJoin (#308)

Author: SimonCropp

apiCount.include.md

@@ -1 +1 @@
-**API count: 522**
+**API count: 524**

api_list.include.md

@@ -367,6 +367,8 @@
  * `StringBuilder Append(StringBuilder, IFormatProvider?, AppendInterpolatedStringHandler)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.append#system-text-stringbuilder-append(system-iformatprovider-system-text-stringbuilder-appendinterpolatedstringhandler@))
  * `StringBuilder Append(StringBuilder, StringBuilder.AppendInterpolatedStringHandler)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.append#system-text-stringbuilder-append(system-text-stringbuilder-appendinterpolatedstringhandler@))
  * `StringBuilder Append(StringBuilder, IFormatProvider?, StringBuilder.AppendInterpolatedStringHandler)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.append#system-text-stringbuilder-append(system-iformatprovider-system-text-stringbuilder-appendinterpolatedstringhandler@))
+ * `StringBuilder AppendJoin<T>(StringBuilder, char, IEnumerable<T>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin-1(system-string-system-collections-generic-ienumerable((-0))))
+ * `StringBuilder AppendJoin<T>(StringBuilder, string, IEnumerable<T>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin-1(system-char-system-collections-generic-ienumerable((-0))))
  * `StringBuilder AppendJoin(StringBuilder, string, string[])` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin(system-string-system-string()))
  * `StringBuilder AppendJoin(StringBuilder, string, Object[])` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin(system-string-system-object()))
  * `StringBuilder AppendJoin(StringBuilder, char, string[])` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin(system-char-system-string()))

readme.md

@@ -12,7 +12,7 @@ The package targets `netstandard2.0` and is designed to support the following ru
  * `net5.0`, `net6.0`, `net7.0`, `net8.0`, `net9.0`, `net10.0`
 
 
-**API count: 522**<!-- singleLineInclude: apiCount. path: /apiCount.include.md -->
+**API count: 524**<!-- singleLineInclude: apiCount. path: /apiCount.include.md -->
 
 
 **See [Milestones](../../milestones?state=closed) for release notes.**
@@ -841,6 +841,8 @@ The class `Polyfill` includes the following extension methods:
  * `StringBuilder Append(StringBuilder, IFormatProvider?, AppendInterpolatedStringHandler)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.append#system-text-stringbuilder-append(system-iformatprovider-system-text-stringbuilder-appendinterpolatedstringhandler@))
  * `StringBuilder Append(StringBuilder, StringBuilder.AppendInterpolatedStringHandler)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.append#system-text-stringbuilder-append(system-text-stringbuilder-appendinterpolatedstringhandler@))
  * `StringBuilder Append(StringBuilder, IFormatProvider?, StringBuilder.AppendInterpolatedStringHandler)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.append#system-text-stringbuilder-append(system-iformatprovider-system-text-stringbuilder-appendinterpolatedstringhandler@))
+ * `StringBuilder AppendJoin<T>(StringBuilder, char, IEnumerable<T>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin-1(system-string-system-collections-generic-ienumerable((-0))))
+ * `StringBuilder AppendJoin<T>(StringBuilder, string, IEnumerable<T>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin-1(system-char-system-collections-generic-ienumerable((-0))))
  * `StringBuilder AppendJoin(StringBuilder, string, string[])` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin(system-string-system-string()))
  * `StringBuilder AppendJoin(StringBuilder, string, Object[])` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin(system-string-system-object()))
  * `StringBuilder AppendJoin(StringBuilder, char, string[])` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin(system-char-system-string()))

src/Polyfill/Polyfill_StringBuilder_AppendJoin.cs

@@ -9,12 +9,25 @@ namespace Polyfills;
 static partial class Polyfill
 {
 
-#if NETSTANDARD2_0|| NETFRAMEWORK
+#if NETSTANDARD2_0 || NETFRAMEWORK
+
+    /// <summary>Concatenates and appends the members of a collection, using the specified separator between each member.</summary>
+    //Link: https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin-1(system-string-system-collections-generic-ienumerable((-0)))
+    public static StringBuilder AppendJoin<T>(
+        this StringBuilder target,
+        char separator,
+        IEnumerable<T> values) =>
+        target.Append(string.Join(separator.ToString(), values));
+
+    /// <summary>Concatenates and appends the members of a collection, using the specified char separator between each member.</summary>
+    //Link: https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin-1(system-char-system-collections-generic-ienumerable((-0)))
+    public static StringBuilder AppendJoin<T>(
+        this StringBuilder target,
+        string separator,
+        IEnumerable<T> values) =>
+        target.Append(string.Join(separator, values));
 
     /// <summary>Concatenates the strings of the provided array, using the specified separator between each string, then appends the result to the current instance of the string builder.</summary>
-    /// <param name="separator">The string to use as a separator. separator is included in the joined strings only if values has more than one element.</param>
-    /// <param name="values">An array that contains the strings to concatenate and append to the current instance of the string builder.</param>
-    /// <returns>A reference to this instance after the append operation has completed.</returns>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin(system-string-system-string())
     public static StringBuilder AppendJoin(
         this StringBuilder target,
@@ -23,9 +36,6 @@ public static StringBuilder AppendJoin(
         target.Append(string.Join(separator, values));
 
     /// <summary>Concatenates the string representations of the elements in the provided array of objects, using the specified separator between each member, then appends the result to the current instance of the string builder.</summary>
-    /// <param name="separator">The string to use as a separator. separator is included in the joined strings only if values has more than one element.</param>
-    /// <param name="values">An array that contains the strings to concatenate and append to the current instance of the string builder.</param>
-    /// <returns>A reference to this instance after the append operation has completed.</returns>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin(system-string-system-object())
     public static StringBuilder AppendJoin(
         this StringBuilder target,
@@ -34,9 +44,6 @@ public static StringBuilder AppendJoin(
         target.Append(string.Join(separator, values));
 
     /// <summary>Concatenates the strings of the provided array, using the specified char separator between each string, then appends the result to the current instance of the string builder.</summary>
-    /// <param name="separator">The character to use as a separator. separator is included in the joined strings only if values has more than one element.</param>
-    /// <param name="values">An array that contains the strings to concatenate and append to the current instance of the string builder.</param>
-    /// <returns>A reference to this instance after the append operation has completed.</returns>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin(system-char-system-string())
     public static StringBuilder AppendJoin(
         this StringBuilder target,
@@ -45,9 +52,6 @@ public static StringBuilder AppendJoin(
         target.Append(string.Join(separator.ToString(), values));
 
     /// <summary>Concatenates the string representations of the elements in the provided array of objects, using the specified char separator between each member, then appends the result to the current instance of the string builder.</summary>
-    /// <param name="separator">The character to use as a separator. separator is included in the joined strings only if values has more than one element.</param>
-    /// <param name="values">An array that contains the strings to concatenate and append to the current instance of the string builder.</param>
-    /// <returns>A reference to this instance after the append operation has completed.</returns>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin(system-char-system-object())
     public static StringBuilder AppendJoin(
         this StringBuilder target,
@@ -56,9 +60,6 @@ public static StringBuilder AppendJoin(
         target.Append(string.Join(separator.ToString(), values));
 
     /// <summary>Concatenates and appends the members of a collection, using the specified char separator between each member.</summary>
-    /// <param name="separator">The character to use as a separator. separator is included in the joined strings only if values has more than one element.</param>
-    /// <param name="values">A collection that contains the objects to concatenate and append to the current instance of the string builder.</param>
-    /// <returns>A reference to this instance after the append operation has completed.</returns>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin-1(system-char-system-collections-generic-ienumerable((-0)))
     public static StringBuilder AppendJoin<T>(
         this StringBuilder target,
@@ -67,9 +68,6 @@ public static StringBuilder AppendJoin<T>(
         target.Append(string.Join(separator.ToString(), values));
 
     /// <summary>Concatenates and appends the members of a collection, using the specified char separator between each member.</summary>
-    /// <param name="separator">The string to use as a separator. separator is included in the concatenated and appended strings only if values has more than one element.</param>
-    /// <param name="values">A collection that contains the objects to concatenate and append to the current instance of the string builder.</param>
-    /// <returns>A reference to this instance after the append operation has completed.</returns>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendjoin#system-text-stringbuilder-appendjoin-1(system-string-system-collections-generic-ienumerable((-0)))
     public static StringBuilder AppendJoin<T>(
         this StringBuilder target,

src/Tests/PolyfillTests_StringBuilder.cs

@@ -106,6 +106,10 @@ public void AppendJoin()
         Assert();
         builder.AppendJoin(',', new object[]{"value1", "value2"});
         Assert();
+        builder.AppendJoin(",", new object[]{"value1", "value2"}.Select(_=>_));
+        Assert();
+        builder.AppendJoin(',', new object[]{"value1", "value2"}.Select(_=>_));
+        Assert();
         // ReSharper disable once RedundantExplicitParamsArrayCreation
         builder.AppendJoin<string>(',', ["value1", "value2"]);
         Assert();