Run tests in CI

Run tests in CI to better demonstrate how to build things.  At the moment
there are some failures. I think I have stashed changes that fix them, but
I think some of them have been introduced by newer tool versions.

Closes: #2
Signed-off-by: Sean Anderson <seanga2@gmail.com>

.github/workflows/doc.yml

@@ -19,6 +19,8 @@ jobs:
       - uses: actions/checkout@v3
         with:
           submodules: true
+      - if: ${{ env.ACT }}
+        run: sudo apt-get update
       - run: sudo apt-get install -y asciidoctor
       - id: config
         uses: actions/configure-pages@v2

.github/workflows/rtl.yml

@@ -0,0 +1,38 @@
+name: Run test suite
+
+on:
+  push
+
+jobs:
+  build:
+    runs-on: ubuntu-24.04
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          submodules: recursive
+      - name: Install dependencies missing in act
+        if: ${{ env.ACT }}
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y python3-dev
+      - name: Get pip cache dir
+        id: pip-cache
+        run: |
+          echo "dir=$(pip cache dir)" >> $GITHUB_OUTPUT
+      - name: Cache pip dependencies
+        uses: actions/cache@v3
+        with:
+          path: ${{ steps.pip-cache.outputs.dir }}
+          key: ${{ runner.os }}-pip-${{ hashFiles('requirements.txt') }}
+          restore-keys: |
+            ${{ runner.os }}-pip-
+      - name: Install dependencies
+        run: |
+          echo "$HOME/.local/bin" >> $GITHUB_PATH
+          sudo apt-get install -y fpga-icestorm iverilog nextpnr-ice40 yosys-dev
+          python3 -m venv venv
+          venv/bin/pip install -r requirements.txt
+      - name: Run tests
+        run: |
+          source venv/bin/activate
+          make -k test

requirements.txt

@@ -0,0 +1,3 @@
+asyncstdlib==3.12.2
+cocotb @ git+https://git@github.com/Forty-Bot/cocotb.git@8810af1a66c461217dc00d0aa47043b8ea130f65
+find_libpython==0.3.0

tb/util.py

@@ -2,6 +2,7 @@
 # Copyright (C) 2022 Sean Anderson <seanga2@gmail.com>
 
 import functools
+import itertools
 import random
 
 import cocotb
@@ -79,28 +80,20 @@ class ReverseList(list):
         return super().__reversed__()
 
 def one_valid():
-    return 1
+    return itertools.repeat(1)
 
 def two_valid():
-    return 2
+    return itertools.repeat(2)
 
 def rand_valid():
-    return random.randrange(3)
+    while True:
+        yield random.randrange(3)
 
-class saw_valid:
-    def __init__(self):
-        self.last = 0
-        # Lie for TestFactory
-        self.__qualname__ = self.__class__.__qualname__
-
-    def __call__(self):
-        self.last += 1
-        if self.last > 2:
-            self.last = 0
-        return self.last
+def saw_valid():
+    return itertools.cycle(range(3))
 
 def with_valids(g, f):
-    for valids in (one_valid, two_valid, rand_valid, saw_valid()):
+    for valids in (one_valid, two_valid, rand_valid, saw_valid):
         async def test(*args, valids=valids, **kwargs):
             await f(*args, valids=valids, **kwargs)
         test.__name__ = f"{f.__name__}_{valids.__qualname__}"
@@ -112,8 +105,7 @@ async def send_recovered_bits(clk, data, valid, bits, valids):
     bits = iter(bits)
     await FallingEdge(clk)
     try:
-        while True:
-            v = valids()
+        for v in valids():
             if v == 0:
                 d = 'XX'
             elif v == 1: