feat(acceptance): #205 AC#2 teensy30 AnalogOutput .dmabuffers gate (#227)

Author: zackees

.github/workflows/acceptance-205.yml

@@ -17,6 +17,7 @@ on:
       - 'crates/fbuild-build/src/teensy/**'
       - 'crates/fbuild-build/src/stm32/**'
       - 'crates/fbuild-build/tests/teensylc_acceptance.rs'
+      - 'crates/fbuild-build/tests/teensy30_acceptance.rs'
       - 'crates/fbuild-build/tests/stm32_acceptance.rs'
       - '.github/workflows/acceptance-205.yml'
 
@@ -37,6 +38,9 @@ jobs:
           - gate: teensyLC
             test_bin: teensylc_acceptance
             test_fn: teensylc_blink_meets_205_acceptance_criteria
+          - gate: teensy30 AnalogOutput
+            test_bin: teensy30_acceptance
+            test_fn: teensy30_analog_output_meets_205_ac2
           - gate: stm32f103c8 SPI
             test_bin: stm32_acceptance
             test_fn: stm32f103c8_blink_with_spi_auto_discovers_library_205_ac4

crates/fbuild-build/tests/teensy30_acceptance.rs

@@ -0,0 +1,152 @@
+//! Acceptance gate for #205 AC#2: teensy30 AnalogOutput sketch.
+//!
+//! Runs the full TeensyOrchestrator build against an inline-tempdir
+//! `AnalogOutput.ino` sketch for the Teensy 3.0 (`teensy30` env) and asserts:
+//!
+//! * `.dmabuffers` section size <= 1 KB (#205 AC#2). The Teensy 3.0 has
+//!   only 16 KB of SRAM; FNET, Snooze, and friends each pull DMAMEM-tagged
+//!   statics (DMA descriptor pools, Ethernet frame buffers, RNG state)
+//!   into the `.dmabuffers` section. If those libraries are linked into a
+//!   simple Arduino `analogWrite` sketch, `.dmabuffers` balloons and the
+//!   build blows the RAM budget. This is the AC#2 gate.
+//! * No `fnet_*`, `snooze_*`, `RadioHead`, or `mbedtls` symbols leaked
+//!   into the linked ELF (#204 / #205 AC#1 regression guard — the same
+//!   forbidden list as `teensylc_acceptance.rs`, complementing teensyLC's
+//!   `.bss <= 3 KB` gate with the teensy30 `.dmabuffers` gate).
+//! * `compile_commands.json` parses and references no `FNET`, `Snooze`,
+//!   `RadioHead`, or `mbedtls` files (#204 root-cause guard).
+//!
+//! Uses the stm32-style inline tempdir `project_dir` so the committed
+//! `tests/platform/teensy30/` fixture is untouched and no
+//! `compile_commands.json` or `.fbuild/` is ever left behind in the repo.
+//!
+//! Run with:
+//! `uv run soldr cargo test -p fbuild-build --test teensy30_acceptance -- --ignored`
+//!
+//! Marked `#[ignore]` because it downloads Teensyduino + arm-gcc on the
+//! first run (cached after) and performs a full firmware build — too
+//! heavy for default `cargo test`.
+//!
+//! LTO-symbol caveat: as with `teensylc_acceptance.rs` and
+//! `stm32_acceptance.rs` (see #223), the Release profile's
+//! `-flto -Os` inlines tiny functions like the sketch's `setup` and
+//! `loop` into their callers and `--gc-sections` strips the
+//! independent symbols. The meaningful signals are therefore the
+//! ELF section size and forbidden-symbol substring checks, not
+//! probes for `setup`/`loop`/`analogWrite` symbols.
+
+use fbuild_build::{BuildOrchestrator, BuildParams};
+use fbuild_core::BuildProfile;
+use fbuild_test_support::{CompileDb, ElfProbe};
+
+#[test]
+#[ignore = "downloads Teensyduino + arm-gcc; CI-only"]
+fn teensy30_analog_output_meets_205_ac2() {
+    // Use a temporary project dir so the committed teensy30 fixture
+    // at tests/platform/teensy30/ stays untouched and no scratch
+    // build artifacts land in the repo.
+    let tmp = tempfile::TempDir::new().unwrap();
+    let project_dir = tmp.path();
+
+    std::fs::write(
+        project_dir.join("platformio.ini"),
+        "[env:teensy30]\n\
+         platform = teensy\n\
+         board = teensy30\n\
+         framework = arduino\n",
+    )
+    .unwrap();
+
+    let src = project_dir.join("src");
+    std::fs::create_dir_all(&src).unwrap();
+    // WHY .ino: the AC#2 sketch is "AnalogOutput" and Teensyduino's
+    // builder treats .ino as Arduino main; this matches the user-facing
+    // `fbuild build teensy30 AnalogOutput` invocation in the #205 body.
+    std::fs::write(
+        src.join("main.ino"),
+        "#include <Arduino.h>\n\
+         void setup() { pinMode(LED_BUILTIN, OUTPUT); }\n\
+         void loop() {\n\
+           for (int v = 0; v < 256; v += 5) {\n\
+             analogWrite(LED_BUILTIN, v);\n\
+             delay(20);\n\
+           }\n\
+         }\n",
+    )
+    .unwrap();
+
+    let build_dir = project_dir.join(".fbuild/build");
+    let params = BuildParams {
+        project_dir: project_dir.to_path_buf(),
+        // WHY env_name = "teensy30": must match the [env:teensy30] key
+        // in the platformio.ini we just wrote. Same root-cause family
+        // as #220 / #221.
+        env_name: "teensy30".to_string(),
+        clean: true,
+        profile: BuildProfile::Release,
+        build_dir,
+        verbose: true,
+        jobs: None,
+        generate_compiledb: true,
+        compiledb_only: false,
+        log_sender: None,
+        symbol_analysis: false,
+        symbol_analysis_path: None,
+        no_timestamp: false,
+        src_dir: None,
+        pio_env: Default::default(),
+        extra_build_flags: Vec::new(),
+        watch_set_cache: None,
+    };
+
+    let result = fbuild_build::teensy::orchestrator::TeensyOrchestrator
+        .build(&params)
+        .expect("teensy30 AnalogOutput build must succeed for AC#2 gate");
+    assert!(result.success, "build did not report success");
+
+    // ── ELF probes (AC#2 + #204 regression guard) ───────────────────────
+    let elf = result
+        .elf_path
+        .as_ref()
+        .expect("teensy build must produce ELF");
+    let probe = ElfProbe::open(elf).expect("ELF parses");
+
+    let dmabuffers = probe
+        .section_size(".dmabuffers")
+        .expect("dmabuffers section query");
+    assert!(
+        dmabuffers <= 1024,
+        "AC#2: .dmabuffers must be <= 1 KB; got {dmabuffers} bytes. \
+         If this fires, the resolver linked FNET/Snooze/RadioHead/mbedtls \
+         DMAMEM-tagged statics into a simple analogWrite sketch — see #204."
+    );
+
+    for forbidden in ["fnet_", "snooze_", "RadioHead", "mbedtls"] {
+        assert!(
+            !probe
+                .has_symbol_containing(forbidden)
+                .expect("symbol query"),
+            "AC#2 / #204: forbidden symbol substring '{forbidden}' present \
+             in ELF — resolver regression"
+        );
+    }
+
+    // ── compile_commands.json probes (#204 root-cause guard) ────────────
+    // WHY use result.compile_database_path: per #226, the pipeline ignores
+    // params.build_dir for the compdb location and roots its build cache
+    // at <project_dir>/.fbuild/build/<env>/<profile>/. The orchestrator
+    // already reports the effective location in BuildResult — trust it
+    // instead of walking the tempdir.
+    let compdb_path = result
+        .compile_database_path
+        .as_ref()
+        .expect("teensy build must report compile_commands.json path");
+    let db = CompileDb::from_path(compdb_path).expect("parse compile_commands.json");
+    let forbidden_hits = db.forbidden_present(&["FNET", "Snooze", "RadioHead", "mbedtls"]);
+    assert!(
+        forbidden_hits.is_empty(),
+        "AC#2 / #204: compile_commands.json must not include any of \
+         FNET/Snooze/RadioHead/mbedtls; found: {:?}",
+        forbidden_hits
+    );
+}