test: set case name from initial filename for a sequence

Port more incremental tests.

test/incremental/assert_function.10.zig

@@ -0,0 +1,27 @@
+pub fn main() void {
+    assert(add(3, 4) == 116);
+}
+
+fn add(a: u32, b: u32) u32 {
+    const x: u32 = blk: {
+        const c = a + b; // 7
+        const d = a + c; // 10
+        const e = d + b; // 14
+        const f = d + e; // 24
+        const g = e + f; // 38
+        const h = f + g; // 62
+        const i = g + h; // 100
+        const j = i + d; // 110
+        break :blk j;
+    };
+    const y = x + a; // 113
+    const z = y + a; // 116
+    return z;
+}
+
+pub fn assert(ok: bool) void {
+    if (!ok) unreachable; // assertion failure
+}
+
+// run
+//