Generate code to reduce duplicate boilerplate code for testing

Author: SpriteOvO

spdlog/build.rs

@@ -1,12 +1,61 @@
+use std::{
+    env,
+    error::Error,
+    fs,
+    path::{Path, PathBuf},
+};
+
 use rustc_version::{version_meta, Channel};
 
-fn main() {
-    // Set cfg flags depending on release channel
-    let channel = match version_meta().unwrap().channel {
+fn main() -> Result<(), Box<dyn Error>> {
+    set_cfg_channel()?;
+    generate_code_test_utils()?;
+    Ok(())
+}
+
+// Set cfg flags depending on release channel
+fn set_cfg_channel() -> Result<(), Box<dyn Error>> {
+    let channel = match version_meta()?.channel {
         Channel::Stable => "CHANNEL_STABLE",
         Channel::Beta => "CHANNEL_BETA",
         Channel::Nightly => "CHANNEL_NIGHTLY",
         Channel::Dev => "CHANNEL_DEV",
     };
-    println!("cargo:rustc-cfg={}", channel)
+    println!("cargo:rustc-cfg={}", channel);
+    Ok(())
+}
+
+// Generate test utils for unit tests, integration tests and doc tests
+//
+// Workaround for the rustdoc bug https://github.com/rust-lang/rust/issues/67295
+fn generate_code_test_utils() -> Result<(), Box<dyn Error>> {
+    let out_dir = PathBuf::from(env::var("OUT_DIR")?).join("test_utils");
+    if !out_dir.is_dir() {
+        fs::create_dir(&out_dir)?;
+    }
+
+    let input = fs::read_to_string("src/test_utils/common.rs")?;
+
+    write_generated_code(
+        out_dir.join("common_for_doc_test.rs"),
+        format!("mod test_utils {{\n{}\n}}", input)
+            .lines()
+            .map(|line| format!("# {}\n", line))
+            .collect::<String>(),
+    )?;
+    write_generated_code(
+        out_dir.join("common_for_unit_test.rs"),
+        input.replace("spdlog::", "crate::"),
+    )?;
+
+    Ok(())
+}
+
+fn write_generated_code(
+    path: impl AsRef<Path>,
+    contents: impl AsRef<[u8]>,
+) -> Result<(), Box<dyn Error>> {
+    println!("cargo:rerun-if-changed={}", path.as_ref().display());
+    fs::write(path, contents)?;
+    Ok(())
 }

spdlog/src/formatter/pattern_formatter/mod.rs

@@ -71,10 +71,10 @@ use crate::{
 /// ```
 /// # use spdlog::formatter::{pattern, PatternFormatter};
 /// use spdlog::info;
-#[doc = include_str!("../../include/doc/test_utils.rs")]
+#[doc = include_str!(concat!(env!("OUT_DIR"), "/test_utils/common_for_doc_test.rs"))]
 ///
 /// let formatter = PatternFormatter::new(pattern!("[{level}] {payload}"));
-/// # let (doctest, sink) = doc_test_utils::echo_logger_from_formatter(
+/// # let (doctest, sink) = test_utils::echo_logger_from_formatter(
 /// #     Box::new(formatter),
 /// #     None
 /// # );
@@ -97,9 +97,9 @@ use crate::{
 /// #     formatter::{pattern, PatternFormatter},
 /// #     info,
 /// # };
-#[doc = include_str!("../../include/doc/test_utils.rs")]
+#[doc = include_str!(concat!(env!("OUT_DIR"), "/test_utils/common_for_doc_test.rs"))]
 /// let formatter = PatternFormatter::new(pattern!("[{{escaped}}] {payload}"));
-/// # let (doctest, sink) = doc_test_utils::echo_logger_from_formatter(
+/// # let (doctest, sink) = test_utils::echo_logger_from_formatter(
 /// #     Box::new(formatter),
 /// #     None
 /// # );
@@ -126,9 +126,9 @@ use crate::{
 /// #     formatter::{pattern, PatternFormatter},
 /// #     info,
 /// # };
-#[doc = include_str!("../../include/doc/test_utils.rs")]
+#[doc = include_str!(concat!(env!("OUT_DIR"), "/test_utils/common_for_doc_test.rs"))]
 /// let formatter = PatternFormatter::new(pattern!("{^[{level}]} {payload}"));
-/// # let (doctest, sink) = doc_test_utils::echo_logger_from_formatter(
+/// # let (doctest, sink) = test_utils::echo_logger_from_formatter(
 /// #     Box::new(formatter),
 /// #     None
 /// # );
@@ -155,7 +155,7 @@ use crate::{
 ///     formatter::{pattern, Pattern, PatternContext, PatternFormatter},
 ///     Record, StringBuf, info
 /// };
-#[doc = include_str!("../../include/doc/test_utils.rs")]
+#[doc = include_str!(concat!(env!("OUT_DIR"), "/test_utils/common_for_doc_test.rs"))]
 ///
 /// #[derive(Default, Clone)]
 /// struct MyPattern;
@@ -175,7 +175,7 @@ use crate::{
 ///     {$mypat} => MyPattern::default,
 /// );
 /// let formatter = PatternFormatter::new(pat);
-/// # let (doctest, sink) = doc_test_utils::echo_logger_from_formatter(
+/// # let (doctest, sink) = test_utils::echo_logger_from_formatter(
 /// #     Box::new(formatter),
 /// #     None
 /// # );
@@ -213,7 +213,7 @@ use crate::{
 /// #     prelude::*,
 /// #     Record, StringBuf,
 /// # };
-#[doc = include_str!("../../include/doc/test_utils.rs")]
+#[doc = include_str!(concat!(env!("OUT_DIR"), "/test_utils/common_for_doc_test.rs"))]
 /// static NEXT_ID: AtomicU32 = AtomicU32::new(0);
 ///
 /// #[derive(Clone)]
@@ -244,7 +244,7 @@ use crate::{
 ///     {$mypat} => MyPattern::new,
 /// );
 /// let formatter = PatternFormatter::new(pat);
-/// # let (doctest, sink) = doc_test_utils::echo_logger_from_formatter(
+/// # let (doctest, sink) = test_utils::echo_logger_from_formatter(
 /// #     Box::new(formatter),
 /// #     None
 /// # );

spdlog/src/include/doc/test_utils.rs

@@ -0,0 +1,46 @@
+// Test utils for unit tests, integration tests and doc tests
+//
+// In this file, you can only use public items from spdlog-rs, as this file will
+// be used from integration tests and doc tests.
+//
+// This file will be handled in `build.rs` for code generation to workaround the
+// rustdoc bug https://github.com/rust-lang/rust/issues/67295
+
+use std::sync::Arc;
+
+use spdlog::{
+    formatter::{Formatter, Pattern, PatternFormatter},
+    prelude::*,
+    sink::WriteSink,
+};
+
+#[must_use]
+pub fn echo_logger_from_pattern(
+    pattern: impl Pattern + Clone + 'static,
+    name: Option<&'static str>,
+) -> (Logger, Arc<WriteSink<Vec<u8>>>) {
+    echo_logger_from_formatter(Box::new(PatternFormatter::new(pattern)), name)
+}
+
+#[must_use]
+pub fn echo_logger_from_formatter(
+    formatter: Box<dyn Formatter>,
+    name: Option<&'static str>,
+) -> (Logger, Arc<WriteSink<Vec<u8>>>) {
+    let sink = Arc::new(
+        WriteSink::builder()
+            .formatter(formatter)
+            .target(Vec::new())
+            .build()
+            .unwrap(),
+    );
+
+    let mut builder = Logger::builder();
+
+    builder.sink(sink.clone());
+    if let Some(name) = name {
+        builder.name(name);
+    }
+
+    (builder.build().unwrap(), sink)
+}

spdlog/src/test_utils/common.rs

@@ -0,0 +1,12 @@
+mod unit_test;
+pub(crate) use unit_test::*;
+
+#[allow(dead_code)]
+mod common {
+    include!(concat!(
+        env!("OUT_DIR"),
+        "/test_utils/common_for_unit_test.rs"
+    ));
+}
+#[allow(unused_imports)]
+pub(crate) use common::*;

spdlog/src/test_utils/mod.rs

@@ -1,3 +1,8 @@
+// Test utils for unit tests only
+//
+// In this file, you can use public or private items from spdlog-rs as you wish,
+// as they will be used from unit tests only.
+
 use std::{env, fmt::Write, fs, path::PathBuf, thread::sleep, time::Duration};
 
 use crate::{