refactor: use czv in czv-python

- Add `file_path` for czv-python count operations
- Refactor tests based on file path instead of data
- Use thiserror in czv
- Update examples to reflect changes

czv-python/Cargo.toml

@@ -12,5 +12,6 @@ crate-type = ["cdylib", "rlib"]
 [dependencies]
 anyhow = "1.0.86"
 csv = "1.3.0"
+czv = { path = "../czv" }
 pyo3 = { version = "0.21.2", features = ["extension-module"] }
 thiserror = "1.0.61"

czv-python/README.md

@@ -1,24 +1,26 @@
 # czv-python
 
-Python library for [czv](https://github.com/rzmk/czv). czv is a library of utility functions for CSV-related data engineering and analysis tasks.
+Python library for [czv](https://github.com/rzmk/czv). czv is a library of CSV-related operations for data engineering and analysis tasks.
+
+-   For a Rust library see [czv](https://github.com/rzmk/czv/tree/main/czv).
+-   For a WebAssembly (JavaScript, TypeScript) library see [czv-wasm](https://github.com/rzmk/czv/tree/main/czv-wasm).
 
 ## Installation and example
 
+To install `czv`, run:
+
 ```bash
 pip install czv
 ```
 
+Let's say we want to print the total number of rows in a 4x3 CSV file `fruits.csv` including the header row:
+
 ```python
 import czv
 
-data = """fruits,price
-apple,2.50
-banana,3.00
-strawberry,1.50"""
+output = czv.row_count(file_path="fruits.csv", include_header_row=True)
 
-output = czv.row_count(data, False)
-
-print(output)
+print(output) # 4
 ```
 
 ## Development

czv-python/czv.pyi

@@ -14,12 +14,7 @@ pip install czv
 ```python
 from czv import row_count
 
-data = \"""fruits,price
-apple,2.50
-banana,3.00
-strawberry,1.50\"""
-
-output = row_count(data, False)
+output = row_count(file_path="fruits.csv")
 
 print(output)
 ```
@@ -27,20 +22,23 @@ print(output)
 """
 
 from typing import Optional
+from pathlib import Path
 
-def row_count(file_data: str, include_header_row: Optional[bool]) -> int:
+def row_count(file_path: Optional[Path], file_data: Optional[str], include_header_row: Optional[bool]) -> int:
     """Returns a count of the total number of rows.
     
     ## Arguments
      
+    * `file_path` - CSV file path.
     * `file_data` - CSV file data.
     * `include_header_row` - Specify whether to include the header row (first row) in the row count. Default is false.
     """
 
-def column_count(file_data: str) -> int:
+def column_count(file_path: Optional[Path], file_data: Optional[str]) -> int:
     """Returns a count of the total number of columns (fields).
     
     ## Arguments
     
+    * `file_path` - CSV file path.
     * `file_data` - CSV file data.
     """

czv-python/examples/simple_row_count.py

@@ -5,6 +5,6 @@ apple,2.50
 banana,3.00
 strawberry,1.50"""
 
-output = czv.row_count(data, False)
+output = czv.row_count(file_data=data, include_header_row=True)
 
-print(output)
+print(output) # 4

czv-python/src/count.rs

@@ -1,33 +1,21 @@
 use crate::Result;
-use csv::ReaderBuilder;
 use pyo3::pyfunction;
+use std::path::PathBuf;
 
-/// Returns a count of the total number of rows.
-///
-/// ## Arguments
-///
-/// * `file_data` - CSV file data.
-/// * `include_header_row` - Specify whether to include the header row (first row) in the row count.
 #[pyfunction]
-pub fn row_count(file_data: String, include_header_row: Option<bool>) -> Result<usize> {
-    let mut rdr = ReaderBuilder::new();
-
-    rdr.has_headers(!include_header_row.unwrap_or(false));
-    return Ok(rdr.from_reader(file_data.as_bytes()).records().count());
+pub fn row_count(
+    file_path: Option<PathBuf>,
+    file_data: Option<String>,
+    include_header_row: Option<bool>,
+) -> Result<usize> {
+    Ok(czv::count::row_count(
+        file_path,
+        file_data,
+        include_header_row.unwrap_or(false),
+    )?)
 }
 
-/// Returns a count of the total number of columns (fields).
-///
-/// ## Arguments
-///
-/// * `file_data` - CSV file data.
 #[pyfunction]
-pub fn column_count(file_data: Option<String>) -> Result<usize> {
-    let rdr = ReaderBuilder::new();
-
-    if let Some(file_data) = file_data {
-        return Ok(rdr.from_reader(file_data.as_bytes()).headers()?.len());
-    } else {
-        bail!("Could not determine a file path or file data for column_count_builder.");
-    }
+pub fn column_count(file_path: Option<PathBuf>, file_data: Option<String>) -> Result<usize> {
+    Ok(czv::count::column_count(file_path, file_data)?)
 }

czv-python/src/lib.rs

@@ -1,3 +1,4 @@
+use ::czv::CzvError as OGError;
 use pyo3::prelude::*;
 
 // Error-handling helpers
@@ -5,6 +6,12 @@ use pyo3::prelude::*;
 #[error("{0}")]
 pub struct CzvError(anyhow::Error);
 
+impl From<OGError> for CzvError {
+    fn from(value: OGError) -> Self {
+        value.into()
+    }
+}
+
 impl From<pyo3::PyErr> for CzvError {
     fn from(value: pyo3::PyErr) -> Self {
         value.into()

czv-python/tests/test_count.py

@@ -10,7 +10,7 @@ class TestCountFunc:
     def test_count(self, file_name, expected):
         """Count the total number of non-header rows."""
 
-        result = czv.row_count(test_data[file_name].read_text())
+        result = czv.row_count(file_path=test_data[file_name])
         assert result == expected
 
     @pytest.mark.parametrize(
@@ -20,5 +20,5 @@ class TestCountFunc:
     def test_include_header_row(self, file_name, expected):
         """Count the total number of rows including the header row."""
 
-        result = czv.row_count(test_data[file_name].read_text(), include_header_row=True)
+        result = czv.row_count(file_path=test_data[file_name], include_header_row=True)
         assert result == expected