Bug 1377351 - Part 3: Expose nsA[C]String::Assign(nsA[C]String&&) overload as take_from to rust, r=froydnj

MozReview-Commit-ID: 4YNPi3iRo78

xpcom/rust/nsstring/src/lib.rs

@@ -179,6 +179,7 @@ macro_rules! define_string_types {
 
         drop = $drop: ident;
         assign = $assign: ident, $fallible_assign: ident;
+        take_from = $take_from: ident, $fallible_take_from: ident;
         append = $append: ident, $fallible_append: ident;
         set_length = $set_length: ident, $fallible_set_length: ident;
         begin_writing = $begin_writing: ident, $fallible_begin_writing: ident;
@@ -270,6 +271,25 @@ macro_rules! define_string_types {
                 }
             }
 
+            /// Take the value of `other` and set `self`, overwriting any value
+            /// currently stored. The passed-in string will be truncated.
+            pub fn take_from(&mut self, other: &mut $AString) {
+                unsafe { $take_from(self, other) };
+            }
+
+            /// Take the value of `other` and set `self`, overwriting any value
+            /// currently stored. If this function fails, the source string will
+            /// be left untouched, otherwise it will be truncated.
+            ///
+            /// Returns Ok(()) on success, and Err(()) if the allocation failed.
+            pub fn fallible_take_from(&mut self, other: &mut $AString) -> Result<(), ()> {
+                if unsafe { $fallible_take_from(self, other) } {
+                    Ok(())
+                } else {
+                    Err(())
+                }
+            }
+
             /// Append the value of `other` into self.
             pub fn append<T: $StringLike + ?Sized>(&mut self, other: &T) {
                 unsafe { $append(self, other.adapt().as_ptr()) };
@@ -776,6 +796,7 @@ define_string_types! {
 
     drop = Gecko_FinalizeCString;
     assign = Gecko_AssignCString, Gecko_FallibleAssignCString;
+    take_from = Gecko_TakeFromCString, Gecko_FallibleTakeFromCString;
     append = Gecko_AppendCString, Gecko_FallibleAppendCString;
     set_length = Gecko_SetLengthCString, Gecko_FallibleSetLengthCString;
     begin_writing = Gecko_BeginWritingCString, Gecko_FallibleBeginWritingCString;
@@ -909,6 +930,7 @@ define_string_types! {
 
     drop = Gecko_FinalizeString;
     assign = Gecko_AssignString, Gecko_FallibleAssignString;
+    take_from = Gecko_TakeFromString, Gecko_FallibleTakeFromString;
     append = Gecko_AppendString, Gecko_FallibleAppendString;
     set_length = Gecko_SetLengthString, Gecko_FallibleSetLengthString;
     begin_writing = Gecko_BeginWritingString, Gecko_FallibleBeginWritingString;
@@ -994,10 +1016,12 @@ extern "C" {
     fn Gecko_FinalizeCString(this: *mut nsACString);
 
     fn Gecko_AssignCString(this: *mut nsACString, other: *const nsACString);
+    fn Gecko_TakeFromCString(this: *mut nsACString, other: *mut nsACString);
     fn Gecko_AppendCString(this: *mut nsACString, other: *const nsACString);
     fn Gecko_SetLengthCString(this: *mut nsACString, length: u32);
     fn Gecko_BeginWritingCString(this: *mut nsACString) -> *mut u8;
     fn Gecko_FallibleAssignCString(this: *mut nsACString, other: *const nsACString) -> bool;
+    fn Gecko_FallibleTakeFromCString(this: *mut nsACString, other: *mut nsACString) -> bool;
     fn Gecko_FallibleAppendCString(this: *mut nsACString, other: *const nsACString) -> bool;
     fn Gecko_FallibleSetLengthCString(this: *mut nsACString, length: u32) -> bool;
     fn Gecko_FallibleBeginWritingCString(this: *mut nsACString) -> *mut u8;
@@ -1005,10 +1029,12 @@ extern "C" {
     fn Gecko_FinalizeString(this: *mut nsAString);
 
     fn Gecko_AssignString(this: *mut nsAString, other: *const nsAString);
+    fn Gecko_TakeFromString(this: *mut nsAString, other: *mut nsAString);
     fn Gecko_AppendString(this: *mut nsAString, other: *const nsAString);
     fn Gecko_SetLengthString(this: *mut nsAString, length: u32);
     fn Gecko_BeginWritingString(this: *mut nsAString) -> *mut u16;
     fn Gecko_FallibleAssignString(this: *mut nsAString, other: *const nsAString) -> bool;
+    fn Gecko_FallibleTakeFromString(this: *mut nsAString, other: *mut nsAString) -> bool;
     fn Gecko_FallibleAppendString(this: *mut nsAString, other: *const nsAString) -> bool;
     fn Gecko_FallibleSetLengthString(this: *mut nsAString, length: u32) -> bool;
     fn Gecko_FallibleBeginWritingString(this: *mut nsAString) -> *mut u16;

xpcom/string/nsSubstring.cpp

@@ -380,6 +380,11 @@ void Gecko_AssignCString(nsACString* aThis, const nsACString* aOther)
   aThis->Assign(*aOther);
 }
 
+void Gecko_TakeFromCString(nsACString* aThis, nsACString* aOther)
+{
+  aThis->Assign(mozilla::Move(*aOther));
+}
+
 void Gecko_AppendCString(nsACString* aThis, const nsACString* aOther)
 {
   aThis->Append(*aOther);
@@ -395,6 +400,11 @@ bool Gecko_FallibleAssignCString(nsACString* aThis, const nsACString* aOther)
   return aThis->Assign(*aOther, mozilla::fallible);
 }
 
+bool Gecko_FallibleTakeFromCString(nsACString* aThis, nsACString* aOther)
+{
+  return aThis->Assign(mozilla::Move(*aOther), mozilla::fallible);
+}
+
 bool Gecko_FallibleAppendCString(nsACString* aThis, const nsACString* aOther)
 {
   return aThis->Append(*aOther, mozilla::fallible);
@@ -425,6 +435,11 @@ void Gecko_AssignString(nsAString* aThis, const nsAString* aOther)
   aThis->Assign(*aOther);
 }
 
+void Gecko_TakeFromString(nsAString* aThis, nsAString* aOther)
+{
+  aThis->Assign(mozilla::Move(*aOther));
+}
+
 void Gecko_AppendString(nsAString* aThis, const nsAString* aOther)
 {
   aThis->Append(*aOther);
@@ -440,6 +455,11 @@ bool Gecko_FallibleAssignString(nsAString* aThis, const nsAString* aOther)
   return aThis->Assign(*aOther, mozilla::fallible);
 }
 
+bool Gecko_FallibleTakeFromString(nsAString* aThis, nsAString* aOther)
+{
+  return aThis->Assign(mozilla::Move(*aOther), mozilla::fallible);
+}
+
 bool Gecko_FallibleAppendString(nsAString* aThis, const nsAString* aOther)
 {
   return aThis->Append(*aOther, mozilla::fallible);