NEWS/test cleanup: correct the dontrun count, add a bf16 source check

NEWS.md

@@ -22,7 +22,6 @@
   License and FLUX.1-schnell is gated, so hosting would cover half the
   catalog and leave two models on a different workflow.
 
-
 * Model residency: `resident_load()`, `resident_activate()`,
   `resident_deactivate()`, `resident_generate()`, `resident_status()`
   and `resident_unload()` keep a pipeline's weights page-locked on the
@@ -54,8 +53,9 @@ Addressing the CRAN review of the 0.2.0 submission:
   for the FLUX, FLUX.2, Z-Image, LTX-2.3 and Gemma3 ports.
 * Examples: 14 of the 23 `\dontrun{}` blocks now run during check, and
   were rewritten to be self-contained instead of referencing undefined
-  objects. The 9 that remain need model weights on disk and are
-  itemised in `cran-comments.md`.
+  objects. The 10 that remain need model weights on disk and are
+  itemised in `cran-comments.md` (the nine left from that pass, plus
+  `resident_load()`, added below).
 * `ddim_scheduler_create()` was uncallable at its documented defaults:
   `beta_schedule` was never passed through `match.arg()`, so `switch()`
   errored on the length-3 default, and the `device` default was a

inst/tinytest/test_bf16_source.R

@@ -0,0 +1,67 @@
+# The bf16 tier reads the unquantized HuggingFace source instead of a
+# built artifact, so the risk it carries is cache layout: does
+# .flux_source_dir() land on a directory the loader can actually open,
+# and is what it finds really bf16?
+#
+# Scope, deliberately: this checks resolution, on-disk dtype, and that
+# flux_open_checkpoint() reports the "full" format that routes to the
+# bf16 load path. It does NOT run a forward pass. bf16 names the storage
+# dtype, and reading it is CPU work, but *computing* in bf16 is GPU-only
+# here -- txt2img_flux2() upcasts to float32 when device == "cpu" -- and
+# materializing the 7.8 GB transformer is not a test-suite job.
+#
+# at_home() gates the whole file: R CMD check machines have no such
+# cache.
+
+library(tinytest)
+library(diffuseR)
+
+if (!at_home()) {
+  exit_file("bf16 source checks need a populated hfhub cache")
+}
+if (!requireNamespace("safetensors", quietly = TRUE)) {
+  exit_file("safetensors not installed")
+}
+
+src <- tryCatch(diffuseR:::.flux_source_dir("flux2"), error = function(e) NULL)
+if (is.null(src)) {
+  exit_file("FLUX.2 bf16 source not in the hfhub cache")
+}
+
+# --- resolution lands somewhere the loader can use --------------------------------
+
+expect_true(dir.exists(src))
+expect_true(file.exists(file.path(src, "config.json")))
+expect_true(length(list.files(src, pattern = "[.]safetensors$")) > 0L)
+
+# The precision router must send bf16 here and NOT to "<prefix>bf16",
+# which is what it did before and why the tier was unreachable.
+prefix <- file.path(tools::R_user_dir("diffuseR", "data"), "flux2-klein-4b-")
+expect_equal(diffuseR:::.flux_model_dir("flux2", "bf16", prefix), src)
+expect_equal(diffuseR:::.flux_model_dir("flux2", "nf4", prefix),
+             paste0(prefix, "nf4"))
+
+# --- what is on disk is actually bf16 ---------------------------------------------
+
+# Read only the safetensors JSON header (8-byte little-endian length,
+# then that many bytes), so this stays cheap and loads no tensors.
+shard <- list.files(src, pattern = "[.]safetensors$", full.names = TRUE)[1]
+con <- file(shard, "rb")
+n <- readBin(con, "integer", n = 1L, size = 8L, endian = "little")
+hdr <- rawToChar(readBin(con, "raw", n = n))
+close(con)
+meta <- jsonlite::fromJSON(hdr)
+meta <- meta[names(meta) != "__metadata__"]
+dtypes <- unique(vapply(meta, function(x) x$dtype, character(1)))
+expect_equal(dtypes, "BF16")
+
+# --- the checkpoint opens and reports the full (unquantized) format ---------------
+
+ckpt <- flux_open_checkpoint(src)
+expect_inherits(ckpt, "ltx23_checkpoint")
+# flux_load_transformer() branches on `format %||% "full"`; a source
+# checkpoint carries no format, which is what selects the bf16 path.
+expect_null(ckpt$format)
+expect_true(length(ckpt$keys) > 0L)
+expect_equal(length(ckpt$keys), length(meta))
+expect_equal(ckpt$config[["_class_name"]], "Flux2Transformer2DModel")

inst/tinytest/test_recommend.R

@@ -216,4 +216,3 @@ expect_error(diffuseR:::.flux_source_dir("nosuch"), pattern = "No bf16 source")
 expect_equal(recommend("ltx", vram_gb = 16)$precision, "nf4")
 expect_true("precision" %in% names(formals(download_ltx2)))
 expect_equal(eval(formals(download_ltx2)$precision), c("nf4", "fp8"))
-