Fix compilation with dip1000

dub.json

@@ -18,6 +18,7 @@
         },
         {
             "name": "unittest",
+            "dflags": ["-preview=dip1000"],
             "sourceFiles": [ "tests/unit/*.d" ]
         }
     ],

source/configy/backend/keyvalue.d

@@ -122,7 +122,7 @@ public class KeyValueMapping : Mapping {
         return Location(this.prefix.length ? this.prefix[0 .. $ - 1] : null);
     }
     public override Type type () const scope @safe nothrow { return Type.Mapping; }
-    public override inout(KeyValueMapping) asMapping () inout scope @safe { return this; }
+    public override inout(KeyValueMapping) asMapping () inout return scope @safe { return this; }
     public override inout(Sequence) asSequence () inout scope @safe { return null; }
     public override inout(Scalar) asScalar () inout scope @safe { return null; }
 
@@ -205,7 +205,7 @@ public class SequenceOrScalar : Sequence, Scalar {
     ///
     public override inout(Mapping) asMapping () inout scope @safe { return null; }
     ///
-    public override inout(SequenceOrScalar) asSequence () inout scope @safe { return this; }
+    public override inout(SequenceOrScalar) asSequence () inout return scope @safe { return this; }
     ///
-    public override inout(SequenceOrScalar) asScalar () inout scope @safe { return this; }
+    public override inout(SequenceOrScalar) asScalar () inout return scope @safe { return this; }
 }

source/configy/backend/multi.d

@@ -64,7 +64,7 @@ public class MultiMapping : Mapping {
     }
 
     ///
-    public override inout(Mapping)  asMapping () inout scope @safe { return this; }
+    public override inout(Mapping)  asMapping () inout return scope @safe { return this; }
     public override inout(Sequence) asSequence () inout scope @safe { return null; }
     public override inout(Scalar)   asScalar () inout scope @safe   { return null; }
 
@@ -118,13 +118,13 @@ private struct MultiMappingBuffer {
     private size_t idx;
 
     /// Adds a node to the buffer - skip any `null` node
-    public void add (scope Mapping node) @safe scope return {
+    public void add (Mapping node) @safe scope return {
         if (node is null) return;
         this.buffer[this.idx++] = node;
     }
 
     /// Returns: A slice of the buffer with all non-null node
-    public Mapping[] opSlice () @safe scope return {
+    public Mapping[] opSlice () @safe return {
         return this.buffer[0 .. this.idx];
     }
 

source/configy/backend/node.d

@@ -219,5 +219,5 @@ public class SimpleScalar : Scalar {
     ///
     public override inout(Sequence) asSequence () inout scope @safe { return null; }
     ///
-    public override inout(SimpleScalar) asScalar () inout scope @safe { return this; }
+    public override inout(SimpleScalar) asScalar () inout return scope @safe { return this; }
 }

source/configy/utils.d

@@ -20,7 +20,7 @@ module configy.utils;
 import std.format;
 
 /// Type of sink used by the `toString`
-package alias SinkType = void delegate (in char[]) @safe;
+package alias SinkType = void delegate (const scope char[]) @safe;
 
 /// Convenience function to extend a path
 package string addPath (string opath, string newPart) @safe pure nothrow
@@ -95,7 +95,7 @@ package struct Colored (T)
         static if (is(typeof(T.init.length) : size_t))
             if (this.value.length == 0) return;
 
-        formattedWrite(sink, "%s%s%s", this.color, this.value, Reset);
+        () @trusted { formattedWrite(sink, "%s%s%s", this.color, this.value, Reset); }();
     }
 }