Re-adding throw helpers to help with inlining.

Author: Stefán J. Sigurðarson

projects/RabbitMQ.Client/client/impl/WireFormatting.cs

@@ -148,7 +148,8 @@ public static int ReadLongstr(ReadOnlySpan<byte> span, out byte[] value)
 
             if (byteCount > int.MaxValue)
             {
-                throw new SyntaxErrorException($"Long string too long; byte length={byteCount}, max={int.MaxValue}");
+                value = null;
+                return ThrowSyntaxErrorException(byteCount);
             }
 
             value = span.Slice(4, (int)byteCount).ToArray();
@@ -183,7 +184,8 @@ public static int ReadShortstr(ReadOnlySpan<byte> span, out string value)
 #endif
             }
 
-            throw new ArgumentOutOfRangeException("span", $"Span has not enough space ({span.Length} instead of {byteCount + 1})");
+            value = null;
+            return ThrowArgumentOutOfRangeException(span.Length, byteCount + 1);
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
@@ -737,9 +739,9 @@ public static int WriteShortstr(Span<byte> span, string val)
                 span[0] = (byte)bytesWritten;
                 return bytesWritten + 1;
             }
-            catch (ArgumentException e)
+            catch (ArgumentException)
             {
-                throw new ArgumentOutOfRangeException($"Value exceeds the maximum allowed length of {maxLength} bytes.", e);
+                return ThrowArgumentOutOfRangeException(nameof(val), val, maxLength);
             }
 #else
             unsafe
@@ -753,9 +755,9 @@ public static int WriteShortstr(Span<byte> span, string val)
                         span[0] = (byte)bytesWritten;
                         return bytesWritten + 1;
                     }
-                    catch (ArgumentException e)
+                    catch (ArgumentException)
                     {
-                        throw new ArgumentOutOfRangeException($"Value exceeds the maximum allowed length of {maxLength} bytes.", e);
+                        return ThrowArgumentOutOfRangeException(nameof(val), val, maxLength);
                     }
                 }
             }
@@ -894,5 +896,20 @@ public static int WriteTimestamp(Span<byte> span, AmqpTimestamp val)
             // See also MethodArgumentReader.ReadTimestamp and AmqpTimestamp itself
             return WriteLonglong(span, (ulong)val.UnixTime);
         }
+
+        public static int ThrowArgumentOutOfRangeException(int orig, int expected)
+        {
+            throw new ArgumentOutOfRangeException("span", $"Span has not enough space ({orig} instead of {expected})");
+        }
+
+        public static int ThrowArgumentOutOfRangeException(string paramName, string val, int maxLength)
+        {
+            throw new ArgumentOutOfRangeException(paramName, val, $"Value exceeds the maximum allowed length of {maxLength} bytes.");
+        }
+
+        public static int ThrowSyntaxErrorException(uint byteCount)
+        {
+            throw new SyntaxErrorException($"Long string too long; byte length={byteCount}, max={int.MaxValue}");
+        }
     }
 }