Merge branch 'release/0.2.2'

.github/workflows/shellcheck.yml

@@ -32,3 +32,4 @@ jobs:
     - name: ShellCheck
       run: |
         ./shellcheck -- x86-64-level
+        ./shellcheck -- tests/x86-64-level.sh

.github/workflows/unit_tests.yml

@@ -0,0 +1,24 @@
+on: [push, pull_request]
+
+name: unit_tests
+
+jobs:
+  checks:
+    if: "! contains(github.event.head_commit.message, '[ci skip]')"
+
+    timeout-minutes: 2
+
+    runs-on: ubuntu-22.04
+
+    name: unit_tests
+
+    strategy:
+      fail-fast: false
+
+    steps:
+    - name: Checkout git repository
+      uses: actions/checkout@v3
+
+    - name: Run unit tests
+      run: |
+        PATH=.:$PATH tests/x86-64-level.sh

Makefile

@@ -0,0 +1,8 @@
+all: shellcheck check
+
+shellcheck:
+	shellcheck x86-64-level
+	shellcheck tests/x86-64-level.sh
+
+check:
+	@PATH=.:${PATH} tests/x86-64-level.sh

NEWS.md

@@ -1,3 +1,22 @@
+# Version 0.2.2 [2023-05-25]
+
+## New Features
+
+ * Now `x86-64-level` asserts that the input CPU flags are of the
+   correct format, which is assumed to be only lower-case letters,
+   digits, and underscores.
+
+## Bug Fixes
+
+ * Calling `x86-64-level --assert=""` would produce error message
+   `merror: command not found` and not the intended `ERROR: Option
+   '--assert' must not be empty`.
+
+## Miscellaneous
+
+ * Add unit tests.
+
+
 # Version 0.2.1 [2023-01-18]
 
  * Now `--assert` reports also on the CPU name.

README.md

@@ -1,8 +1,9 @@
 [![shellcheck](https://github.com/HenrikBengtsson/x86-64-level/actions/workflows/shellcheck.yml/badge.svg)](https://github.com/HenrikBengtsson/x86-64-level/actions/workflows/shellcheck.yml)
+[![unit_tests](https://github.com/HenrikBengtsson/x86-64-level/actions/workflows/unit_tests.yml/badge.svg)](https://github.com/HenrikBengtsson/x86-64-level/actions/workflows/unit_tests.yml)
 
 # x86-64-level - Get the x86-64 Microarchitecture Level on the Current Machine
 
-TL;DR: The `x86-64-level` tool identifies the current CPU supports
+TL;DR: The `x86-64-level` tool identifies if the current CPU supports
 x86-64-v1, x86-64-v2, x86-64-v3, or x86-64-v4, e.g.
 
 ```sh
@@ -14,7 +15,7 @@ $ x86-64-level
 # Background
 
 **x86-64** is a 64-bit version of the x86 CPU instruction set
-supported by AMD and Intel CPUs among others.  Since the first
+supported by AMD and Intel CPUs, among others.  Since the first
 generations of CPUs, more low-level CPU features have been added over
 the years.  The x86-64 CPU features can be grouped into four [CPU
 microarchitecture levels]:
@@ -28,8 +29,9 @@ microarchitecture levels]:
 
 The x86-64-v1 level is the same as the original, baseline x86-64
 level.  These levels are subsets of each other, i.e. x86-64-v1 ⊂
-x86-64-v2 ⊂ x86-64-v3 ⊂ x86-64-v4.
-
+x86-64-v2 ⊂ x86-64-v3 ⊂ x86-64-v4.  For a CPU to support a level, it
+must support _all_ CPU features of that version level, and, because
+they are subsets of each other, all those of the lower versions.
 
 Software can be written so that they use the most powerful set of CPU
 features available.  This optimization happens at compile time and
@@ -44,12 +46,18 @@ might get something like:
 address 0x2b3a8b234ccd, cause 'illegal operand'
 ```
 
+or
+
+```
+Illegal instruction (core dumped)
+```
+
 This is because the older CPU does not understand one of the CPU
-instructions ("operands").  Note that the software might not crash each
-time.  It will only do so if it reach the part of the code that uses
-the never CPU instructions.
+instructions ("operands").  Note that the software might not crash
+each time.  It will only do so if it reaches the part of the code that
+uses a CPU instruction that is not recognized by the current CPU.
 
-In contrast, if we compile the software on the older x86-64-v3
+In contrast, if we compile the software towards the older x86-64-v3
 machine, the produced binary will only use x86-64-v3 instructions and
 will therefor also run on the newer x86-64-v4 machine.
 
@@ -65,8 +73,8 @@ illegal operation' problem.
 
 ## Finding CPU's x86-64 level
 
-This tool, `x86-64-level`, allows you to query the which x86-64 level
-the CPU on current machine supports.  For example,
+This tool, `x86-64-level`, allows you to query which x86-64 level the
+CPU on current machine supports.  For example,
 
 ```sh
 $ x86-64-level
@@ -81,12 +89,13 @@ $ echo "x86-64-v${level}"
 x86-64-v3
 ```
 
-If you want to know an "explanation", specify option `--verbose`, e.g.
+If you want to get an explanation for the identified level, specify
+option `--verbose`, e.g.
 
 ```sh
 $ x86-64-level --verbose
 Identified x86-64-v3, because x86-64-v4 requires 'avx512f', which
-this CPU [Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz] does not support
+is not supported by this CPU [Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz]
 3
 ```
 
@@ -123,7 +132,7 @@ x86-64-level --assert=4 || exit 1
 
 This will output that error message (to the standard error) and exit
 the script with exit code 1, if, and only if, the current machine does
-not support x86-64-v4. In all other cases, it continue silently.
+not support x86-64-v4. In all other cases, it continues silently.