fix: dont accidentally wipe pyproject.toml on init (#1775)

Fixes #1770

src/cli/init.rs

@@ -335,8 +335,7 @@ pub async fn execute(args: Args) -> miette::Result<()> {
             }
 
             // Create a 'pyproject.toml' manifest
-        }
-        if pyproject {
+        } else if pyproject {
             let rv = env
                 .render_named_str(
                     consts::PYPROJECT_MANIFEST,

tests/common/builders.rs

@@ -78,6 +78,12 @@ impl InitBuilder {
         self.args.channels = Some(vec![]);
         self
     }
+
+    /// Instruct init which manifest format to use
+    pub fn with_format(mut self, format: init::ManifestFormat) -> Self {
+        self.args.format = Some(format);
+        self
+    }
 }
 
 impl IntoFuture for InitBuilder {

tests/common/mod.rs

@@ -194,7 +194,25 @@ impl PixiControl {
     }
 
     pub fn manifest_path(&self) -> PathBuf {
-        self.project_path().join(consts::PROJECT_MANIFEST)
+        // Either pixi.toml or pyproject.toml
+        if self.project_path().join(consts::PROJECT_MANIFEST).exists() {
+            return self.project_path().join(consts::PROJECT_MANIFEST);
+        } else if self
+            .project_path()
+            .join(consts::PYPROJECT_MANIFEST)
+            .exists()
+        {
+            return self.project_path().join(consts::PYPROJECT_MANIFEST);
+        } else {
+            return self.project_path().join(consts::PROJECT_MANIFEST);
+        }
+    }
+
+    /// Get the manifest contents
+    pub fn manifest_contents(&self) -> miette::Result<String> {
+        std::fs::read_to_string(self.manifest_path())
+            .into_diagnostic()
+            .context("failed to read manifest")
     }
 
     /// Initialize pixi project inside a temporary directory. Returns a

tests/init_tests.rs

@@ -2,8 +2,9 @@ mod common;
 
 use std::str::FromStr;
 
+use pixi::cli;
 use pixi_manifest::FeaturesExt;
-use rattler_conda_types::{NamedChannelOrUrl, Version};
+use rattler_conda_types::{NamedChannelOrUrl, Platform, Version};
 
 use crate::common::PixiControl;
 
@@ -76,6 +77,37 @@ async fn default_channel() {
     )
 }
 
+// Test the initialization from an existing pyproject.toml file without the pixi information
+#[tokio::test]
+async fn init_from_existing_pyproject_toml() {
+    let pixi = PixiControl::new().unwrap();
+
+    // Copy the pyproject.toml file to the project directory
+    let project_path = pixi.project_path();
+    let pyproject_toml = project_path.join("pyproject.toml");
+    let pyproject_toml_contents = include_str!("pixi_tomls/pyproject_no_pixi.toml");
+    std::fs::write(&pyproject_toml, pyproject_toml_contents).unwrap();
+
+    // Init a new project
+    pixi.init()
+        .with_format(cli::init::ManifestFormat::Pyproject)
+        .await
+        .unwrap();
+
+    // Check if the new manifest still contains all the same data as before
+    assert!(pixi
+        .manifest_contents()
+        .unwrap()
+        .contains(pyproject_toml_contents));
+
+    // Check if the new manifest is readable by pixi and contains the default values
+    let project = pixi.project().unwrap();
+    assert!(project
+        .default_environment()
+        .platforms()
+        .contains(&Platform::current()));
+}
+
 // TODO: enable and fix this test when we fix the global config loading
 // #[tokio::test]
 // async fn default_pypi_config() {

tests/pixi_tomls/pyproject_no_pixi.toml

@@ -0,0 +1,41 @@
+[build-system]
+build-backend = "setuptools.build_meta"
+requires = ["setuptools>=61", "setuptools_scm[toml]>=7"]
+
+[project]
+authors = [{ name = "ORGNAME", email = "[email protected]" }]
+classifiers = ["Development Status :: 1 - Planning"]
+dependencies = ["numpy"]
+description = "TEST"
+dynamic = ["version"]
+license.file = "LICENSE"
+name = "foo"
+readme = "README.md"
+requires-python = ">=3.10"
+
+[project.optional-dependencies]
+dev = ["pytest >=6", "pytest-cov >=3", "pre-commit"]
+test = ["pytest >=6", "pytest-cov >=3", "mypy"]
+
+[project.urls]
+Homepage = "https://github.com/ORGNAME/foo"
+
+[tool.setuptools_scm]
+write_to = "src/foo/_version.py"
+
+
+[tool.pytest.ini_options]
+addopts = ["-ra", "--showlocals", "--strict-markers", "--strict-config"]
+filterwarnings = ["error"]
+log_cli_level = "INFO"
+minversion = "6.0"
+testpaths = ["tests"]
+xfail_strict = true
+
+
+[tool.coverage]
+report.exclude_also = ['\.\.\.', 'if typing.TYPE_CHECKING:']
+run.source = ["foo"]
+
+[tool.mypy]
+files = ["src", "tests"]