From 48dbd175c0578021605d4c23de48b56944ee26cc Mon Sep 17 00:00:00 2001
From: Olivier Lacroix <olivier.lacroix@m4x.org>
Date: Mon, 15 Apr 2024 18:23:57 +1000
Subject: [PATCH] feat: Add option to init with a pyproject.toml (#1188)

---
 docs/advanced/pyproject_toml.md | 18 ++++--------
 docs/reference/cli.md           |  1 +
 src/cli/init.rs                 | 52 +++++++++++++++++++++++++++++++++
 tests/common/mod.rs             |  2 ++
 4 files changed, 60 insertions(+), 13 deletions(-)

diff --git a/docs/advanced/pyproject_toml.md b/docs/advanced/pyproject_toml.md
index e6158919b..c1c0a99e8 100644
--- a/docs/advanced/pyproject_toml.md
+++ b/docs/advanced/pyproject_toml.md
@@ -7,21 +7,13 @@ We don't advise to use the `pyproject.toml` file for anything else than python p
 
 ## Initial setup of the `pyproject.toml` file
 
-When you already have a `pyproject.toml` file in your project, you can add the following section to it:
+When you already have a `pyproject.toml` file in your project, you can run `pixi init` in a that folder. Pixi will automatically
 
-```toml
-[tool.pixi.project]
-channels = ["conda-forge"]
-platforms = ["linux-64", "osx-arm64", "osx-64", "win-64"]
-```
-
-This is the minimum requirement for pixi to understand and parse the project.
-
-However, it is recommended you use `pixi init` in a folder that has a `pyproject.toml` file. Pixi will automatically
-
-- Add the above `[tool.pixi.project]` section to the file, auto-detecting your current platform;
+- Add a `[tool.pixi.project]` section to the file, with the platform and channel information required by pixi;
 - Add the current project as an editable pypi dependency;
-- Add some defaults to the `.gitignore` and `.gitattributes` file.
+- Add some defaults to the `.gitignore` and `.gitattributes` files.
+
+If you do not have an existing `pyproject.toml` file , you can run `pixi init --pyproject` in your project folder. In that case, pixi will create a `pyproject.toml` manifest from scratch with some sane defaults.
 
 ## Python dependency
 
diff --git a/docs/reference/cli.md b/docs/reference/cli.md
index 53d4c8881..a11fd7444 100644
--- a/docs/reference/cli.md
+++ b/docs/reference/cli.md
@@ -31,6 +31,7 @@ It also supports the [`pyproject.toml`](../advanced/pyproject_toml.md) file, if
 - `--channel <CHANNEL> (-c)`: specify a channel that the project uses. Defaults to `conda-forge`. (Allowed to be used more than once)
 - `--platform <PLATFORM> (-p)`: specify a platform that the project supports. (Allowed to be used more than once)
 - `--import <ENV_FILE> (-i)`: Import an existing conda environment file, e.g. `environment.yml`.
+- `--pyproject`: Create a `pyproject.toml` manifest, rather than a `pixi.toml` manifest. Recommended for a python project.
 
 !!! info "Importing an environment.yml"
   When importing an environment, the `pixi.toml` will be created with the dependencies from the environment file.
diff --git a/src/cli/init.rs b/src/cli/init.rs
index 8141bc7a7..0d7202837 100644
--- a/src/cli/init.rs
+++ b/src/cli/init.rs
@@ -31,6 +31,10 @@ pub struct Args {
     /// Environment.yml file to bootstrap the project.
     #[arg(short = 'i', long = "import")]
     pub env_file: Option<PathBuf>,
+
+    /// Create a pyproject.toml manifest instead of a pixi.toml manifest
+    #[arg(long, conflicts_with = "env_file")]
+    pub pyproject: bool,
 }
 
 /// The pixi.toml template
@@ -53,6 +57,8 @@ platforms = {{ platforms }}
 "#;
 
 /// The pyproject.toml template
+///
+/// This is injected into an existing pyproject.toml
 const PYROJECT_TEMPLATE: &str = r#"
 [tool.pixi.project]
 channels = {{ channels }}
@@ -69,6 +75,36 @@ default = { solve-group = "default" }
 {{env}} = { features = {{ features }}, solve-group = "default" }
 {%- endfor %}
 
+[tool.pixi.tasks]
+
+"#;
+
+/// The pyproject.toml template
+///
+/// This is used to create a pyproject.toml from scratch
+const NEW_PYROJECT_TEMPLATE: &str = r#"[project]
+name = "{{ name }}"
+version = "{{ version }}"
+description = "Add a short description here"
+{%- if author %}
+authors = [{name = "{{ author[0] }}", email = "{{ author[1] }}"}]
+{%- endif %}
+requires-python = ">= 3.11"
+dependencies = []
+
+[build-system]
+requires = ["setuptools"]
+build-backend = "setuptools.build_meta"
+
+[tool.pixi.project]
+channels = {{ channels }}
+platforms = {{ platforms }}
+
+[tool.pixi.pypi-dependencies]
+{{ name }} = { path = ".", editable = true }
+
+[tool.pixi.tasks]
+
 "#;
 
 const GITIGNORE_TEMPLATE: &str = r#"# pixi environments
@@ -214,6 +250,22 @@ pub async fn execute(args: Args) -> miette::Result<()> {
                 }
             }
 
+        // Create a 'pyproject.toml' manifest
+        } else if args.pyproject {
+            let rv = env
+                .render_named_str(
+                    consts::PYPROJECT_MANIFEST,
+                    NEW_PYROJECT_TEMPLATE,
+                    context! {
+                        name => default_name,
+                        version,
+                        author,
+                        channels,
+                        platforms
+                    },
+                )
+                .unwrap();
+            fs::write(&pyproject_manifest_path, rv).into_diagnostic()?;
         // Create a 'pixi.toml' manifest
         } else {
             // Check if the 'pixi.toml' file doesn't already exist. We don't want to overwrite it.
diff --git a/tests/common/mod.rs b/tests/common/mod.rs
index b9ffa7a86..bc2a40f79 100644
--- a/tests/common/mod.rs
+++ b/tests/common/mod.rs
@@ -196,6 +196,7 @@ impl PixiControl {
                 channels: None,
                 platforms: Vec::new(),
                 env_file: None,
+                pyproject: false,
             },
         }
     }
@@ -209,6 +210,7 @@ impl PixiControl {
                 channels: None,
                 platforms,
                 env_file: None,
+                pyproject: false,
             },
         }
     }