Merge branch 'ryu'

.github/workflows/rust_ryu_tests.yml

@@ -0,0 +1,21 @@
+name: Rust - test ryu feature
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+    branches: [ "main" ]
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Run the tests for the ryu feature set
+      run: cargo test --features ryu --test '*'

Cargo.toml

@@ -20,6 +20,7 @@ js-sys = {version = "0.3.64", optional = true}
 wasm-bindgen = {version = "0.2.87", optional = true}
 serde = {version = "1.0.193", features = ["derive"], optional = true}
 rust_xlsxwriter_derive = {version = "0.2.0", optional = true}
+ryu = {version = "1.0.18", optional = true}
 
 [dev-dependencies]
 pretty_assertions = "1.3.0"
@@ -47,6 +48,12 @@ serde = ["dep:serde", "dep:rust_xlsxwriter_derive"]
 # `wasm`: Enable wasm/Javascript compilation.
 wasm = ["js-sys", "wasm-bindgen"]
 
+# `ryu`: Adds a dependency on `ryu`. This speeds up writing numeric worksheet
+# cells for large data files. It gives a performance boost above 300,000 numeric
+# cells and can be up to 30% faster than the default number formatting for
+# 5,000,000 numeric cells.
+ryu = ["dep:ryu"]
+
 # `test-resave`: Developer only testing feature.
 test-resave = []
 

README.md

@@ -120,6 +120,11 @@ frequently.
 - `wasm`: Adds a dependency on `js-sys` and `wasm-bindgen` to allow compilation
   for wasm/JavaScript targets.
 
+- `ryu`: Adds a dependency on `ryu`. This speeds up writing numeric
+  worksheet cells for large data files. It gives a performance boost above
+  300,000 numeric cells and can be up to 30% faster than the default number
+  formatting for 5,000,000 numeric cells.
+
 ## Release notes
 
 Recent changes:

examples/app_perf_test.rs

@@ -5,13 +5,19 @@
 //! Simple performance test for rust_xlsxwriter.
 
 use rust_xlsxwriter::{Workbook, XlsxError};
+use std::env;
 
 fn main() -> Result<(), XlsxError> {
-    let mut workbook = Workbook::new();
-    let worksheet = workbook.add_worksheet();
+    let args: Vec<String> = env::args().collect();
 
-    let row_max = 4000;
     let col_max = 50;
+    let row_max = match args.get(1) {
+        Some(arg) => arg.parse::<u32>().unwrap_or(4_000),
+        None => 4_000,
+    };
+
+    let mut workbook = Workbook::new();
+    let worksheet = workbook.add_worksheet();
 
     for row in 0..row_max {
         for col in 0..col_max {

examples/app_perf_test2.rs

@@ -5,16 +5,22 @@
 //! Simple performance test for rust_xlsxwriter.
 
 use rust_xlsxwriter::{Workbook, XlsxError};
+use std::env;
 
 fn main() -> Result<(), XlsxError> {
+    let args: Vec<String> = env::args().collect();
+
     let mut workbook = Workbook::new();
 
+    let col_max = 50;
+    let row_max = match args.get(1) {
+        Some(arg) => arg.parse::<u32>().unwrap_or(4_000),
+        None => 4_000,
+    };
+
     for _ in 0..4 {
         let worksheet = workbook.add_worksheet();
 
-        let row_max = 4000;
-        let col_max = 50;
-
         for row in 0..row_max {
             for col in 0..col_max {
                 worksheet.write_string(row, col, "Foo")?;

examples/app_perf_test3.rs

@@ -5,16 +5,22 @@
 //! Simple performance test for rust_xlsxwriter.
 
 use rust_xlsxwriter::{Workbook, XlsxError};
+use std::env;
 
 fn main() -> Result<(), XlsxError> {
+    let args: Vec<String> = env::args().collect();
+
     let mut workbook = Workbook::new();
 
+    let col_max = 50;
+    let row_max = match args.get(1) {
+        Some(arg) => arg.parse::<u32>().unwrap_or(4_000),
+        None => 4_000,
+    };
+
     for _ in 0..4 {
         let worksheet = workbook.add_worksheet();
 
-        let row_max = 4000;
-        let col_max = 50;
-
         for row in 0..row_max {
             for col in 0..col_max {
                 worksheet.write_number(row, col, 12345.0)?;

src/lib.rs

@@ -174,7 +174,10 @@
 //!   easier to write.
 //! - `wasm`: Adds a dependency on `js-sys` and `wasm-bindgen` to allow
 //!   compilation for wasm/JavaScript targets.
-//!
+//! - `ryu`: Adds a dependency on `ryu`. This speeds up writing numeric
+//!   worksheet cells for large data files. It gives a performance boost above
+//!   300,000 numeric cells and can be up to 30% faster than the default number
+//!   formatting for 5,000,000 numeric cells.
 //!
 mod app;
 mod content_types;

src/worksheet.rs

@@ -13668,6 +13668,15 @@ impl Worksheet {
     fn write_number_cell(&mut self, row: RowNum, col: ColNum, number: f64, xf_index: u32) {
         let col_name = Self::col_to_name(&mut self.col_names, col);
 
+        // Use the optional ryu crate to format f64 cell number data as a
+        // string. Note, the the slightly faster `format_finite()` buffer
+        // function is safe to use here since nan/inf numbers are filtered out
+        // at the `store_number()` level and written as strings.
+        #[cfg(feature = "ryu")]
+        let mut buffer = ryu::Buffer::new();
+        #[cfg(feature = "ryu")]
+        let number = buffer.format_finite(number);
+
         if xf_index > 0 {
             write!(
                 &mut self.writer.xmlfile,

tests/integration/common/mod.rs

@@ -340,6 +340,14 @@ fn compare_xlsx_files(
             exp_xml_string = DIGITS.replace_all(&exp_xml_string, "").to_string();
         }
 
+        // The option ryu crate adds a trailing ".0" at the end of integer
+        // values stored as float, so that 1234 in Excel/std lib becomes 1234.0.
+        // The following fixes that in the generated file to allow comparison.
+        #[cfg(feature = "ryu")]
+        if filename.starts_with("xl/worksheets/sheet") {
+            got_xml_string = got_xml_string.replace(".0</v>", "</v>");
+        }
+
         // Convert the xml strings to vectors for easier comparison.
         let mut exp_xml_vec;
         let mut got_xml_vec;