66 – Bad length in value of T[a..b] = scalar

When a slice is assigned by a scalar, the value of the assignment expression has the length of the whole array, not that of the slice.
----------
import std.stdio;
void show(int[] s) {
 foreach (int i; s) {
 writef("%d ", i);
 }
 writefln();
}
void main() {
 int[] qwert = new int[6];
 int[] yuiop;
 yuiop = qwert[2..5] = 3;
 show(yuiop);
 show(qwert[2..5] = 4);
 show(qwert[2..5]);
 show(qwert);
 show(yuiop[2..5] = qwert[1..4]);
 yuiop = qwert[2..5];
 show(yuiop[1..3] = 6);
 writefln((yuiop[1..3] = 7).length);
}
----------
Output:
3 3 3 0 0 0
4 4 4 0 0 0
4 4 4
0 0 4 4 4 0
0 4 4
6 6 4
3
Expected output:
3 3 3
4 4 4
4 4 4
0 0 4 4 4 0
0 4 4
6 6
2
A testcase (array_chain.d) is also included in my DStress contribution apparently still waiting to be added (see bug 63).

Fixed in 0.151.
Also, unless I'm mistaken, there is a bug in that test code: you have "show(yuiop[2..5] = qwert[1..4]);" at a point where yuiop's length is 3. Shouldn't that read "show(yuiop = qwert[1..4]);"? I get your expected output after that change.

You're right that the testcase is buggy. However, the point was to compare the behaviour when copying a slice to a slice, whereas your proposed change turns it into a reference assignment.
A better corretion is simply to add
 yuiop.length = 6;
before that line.