More notes

Author: blaginin

datafusion/common/src/config.rs

@@ -38,7 +38,7 @@ use crate::{DataFusionError, Result};
 ///    /// Amazing config
 ///    pub struct MyConfig {
 ///        /// Field 1 doc
-///        field1: String, default = "".to_string()
+///        field1: String, transform = str::to_lowercase, default = "".to_string()
 ///
 ///        /// Field 2 doc
 ///        field2: usize, default = 232
@@ -67,9 +67,12 @@ use crate::{DataFusionError, Result};
 ///     fn set(&mut self, key: &str, value: &str) -> Result<()> {
 ///         let (key, rem) = key.split_once('.').unwrap_or((key, ""));
 ///         match key {
-///             "field1" => self.field1.set(rem, value),
-///             "field2" => self.field2.set(rem, value),
-///             "field3" => self.field3.set(rem, value),
+///             "field1" => {
+///                 let value = str::to_lowercase(value);
+///                 self.field1.set(rem, value)
+///             },
+///             "field2" => self.field2.set(rem, value.as_ref()),
+///             "field3" => self.field3.set(rem, value.as_ref()),
 ///             _ => _internal_err!(
 ///                 "Config value \"{}\" not found on MyConfig",
 ///                 key
@@ -102,15 +105,14 @@ use crate::{DataFusionError, Result};
 /// ```
 ///
 /// NB: Misplaced commas may result in nonsensical errors
-///
 #[macro_export]
 macro_rules! config_namespace {
     (
      $(#[doc = $struct_d:tt])*
      $vis:vis struct $struct_name:ident {
         $(
         $(#[doc = $d:tt])*
-        $field_vis:vis $field_name:ident : $field_type:ty, $(transform = $tf:expr,)? default = $default:expr
+        $field_vis:vis $field_name:ident : $field_type:ty, $(transform = $transform:expr,)? default = $default:expr
         )*$(,)*
     }
     ) => {
@@ -131,7 +133,7 @@ macro_rules! config_namespace {
                 match key {
                     $(
                        stringify!($field_name) => {
-                           $(let value = $tf(value);)?
+                           $(let value = $transform(value);)?
                            self.$field_name.set(rem, value.as_ref())
                        },
                     )*
@@ -160,6 +162,20 @@ macro_rules! config_namespace {
     }
 }
 
+config_namespace! {
+   /// Amazing config
+   pub struct MyConfig {
+       /// Field 1 doc
+       field1: String, transform = str::to_lowercase, default = "".to_string()
+
+       /// Field 2 doc
+       field2: usize, default = 232
+
+       /// Field 3 doc
+       field3: Option<usize>, default = None
+   }
+}
+
 config_namespace! {
     /// Options related to catalog and directory scanning
     ///
@@ -220,7 +236,8 @@ config_namespace! {
 
         /// Configure the SQL dialect used by DataFusion's parser; supported values include: Generic,
         /// MySQL, PostgreSQL, Hive, SQLite, Snowflake, Redshift, MsSQL, ClickHouse, BigQuery, and Ansi.
-        pub dialect: String, default = "generic".to_string() // no need to lowercase because this is handled by [`sqlparser::dialect_from_str`]
+        pub dialect: String, default = "generic".to_string() // no need to lowercase because
+        // [`sqlparser::dialect_from_str`] is case-insensitive
 
         /// If true, permit lengths for `VARCHAR` such as `VARCHAR(20)`, but
         /// ignore the length. If false, error if a `VARCHAR` with a length is
@@ -998,7 +1015,6 @@ macro_rules! config_field {
                         Box::new(DataFusionError::External(Box::new(e))),
                     )
                 })?;
-
                 Ok(())
             }
         }

datafusion/core/tests/config_from_env.rs

@@ -21,9 +21,8 @@ use std::env;
 #[test]
 fn from_env() {
     // Note: these must be a single test to avoid interference from concurrent execution
-
     let env_key = "DATAFUSION_OPTIMIZER_FILTER_NULL_JOIN_KEYS";
-    // valid testing
+    // valid testing in different cases
     for bool_option in ["true", "TRUE", "True"] {
         env::set_var(env_key, bool_option);
         let config = ConfigOptions::from_env().unwrap();