use an enum to statically type --lines-changed-only

Author: 2bndy5

cpp-linter-lib/src/clang_tools/clang_format.rs

@@ -8,7 +8,10 @@ use serde::Deserialize;
 use serde_xml_rs::de::Deserializer;
 
 // project-specific crates/modules
-use crate::common_fs::{get_line_cols_from_offset, FileObj};
+use crate::{
+    cli::LinesChangedOnly,
+    common_fs::{get_line_cols_from_offset, FileObj},
+};
 
 /// A Structure used to deserialize clang-format's XML output.
 #[derive(Debug, Deserialize, PartialEq)]
@@ -62,7 +65,7 @@ pub fn run_clang_format(
     cmd: &mut Command,
     file: &FileObj,
     style: &str,
-    lines_changed_only: u8,
+    lines_changed_only: &LinesChangedOnly,
 ) -> FormatAdvice {
     cmd.args(["--style", style, "--output-replacements-xml"]);
     let ranges = file.get_ranges(lines_changed_only);

cpp-linter-lib/src/clang_tools/clang_tidy.rs

@@ -12,7 +12,10 @@ use regex::Regex;
 use serde::Deserialize;
 
 // project-specific modules/crates
-use crate::common_fs::{normalize_path, FileObj};
+use crate::{
+    cli::LinesChangedOnly,
+    common_fs::{normalize_path, FileObj},
+};
 
 /// Used to deserialize a JSON compilation database
 #[derive(Deserialize, Debug)]
@@ -169,7 +172,7 @@ pub fn run_clang_tidy(
     cmd: &mut Command,
     file: &FileObj,
     checks: &str,
-    lines_changed_only: u8,
+    lines_changed_only: &LinesChangedOnly,
     database: &Option<PathBuf>,
     extra_args: &Option<Vec<&str>>,
     database_json: &Option<CompilationDatabase>,
@@ -185,7 +188,7 @@ pub fn run_clang_tidy(
             cmd.args(["--extra-arg", format!("\"{}\"", arg).as_str()]);
         }
     }
-    if lines_changed_only > 0 {
+    if *lines_changed_only != LinesChangedOnly::Off {
         let ranges = file.get_ranges(lines_changed_only);
         let filter = format!(
             "[{{\"name\":{:?},\"lines\":{:?}}}]",

cpp-linter-lib/src/clang_tools/mod.rs

@@ -10,7 +10,10 @@ use which::{which, which_in};
 
 // project-specific modules/crates
 use super::common_fs::FileObj;
-use crate::logger::{end_log_group, start_log_group};
+use crate::{
+    cli::LinesChangedOnly,
+    logger::{end_log_group, start_log_group},
+};
 pub mod clang_format;
 use clang_format::{run_clang_format, FormatAdvice};
 pub mod clang_tidy;
@@ -80,7 +83,7 @@ pub fn capture_clang_tools_output(
     version: &str,
     tidy_checks: &str,
     style: &str,
-    lines_changed_only: u8,
+    lines_changed_only: &LinesChangedOnly,
     database: Option<PathBuf>,
     extra_args: Option<Vec<&str>>,
 ) -> (Vec<FormatAdvice>, Vec<TidyAdvice>) {

cpp-linter-lib/src/cli.rs

@@ -6,6 +6,17 @@ use std::fs;
 use clap::builder::FalseyValueParser;
 use clap::{Arg, ArgAction, ArgMatches, Command};
 
+/// An enum to describe `--lines-changed-only` CLI option's behavior.
+#[derive(PartialEq)]
+pub enum LinesChangedOnly {
+    /// All lines are scanned
+    Off,
+    /// Only lines in the diff are scanned
+    Diff,
+    /// Only lines in the diff with additions are scanned.
+    On,
+}
+
 /// Builds and returns the Command Line Interface's argument parsing object.
 pub fn get_arg_parser() -> Command {
     Command::new("cpp-linter")

cpp-linter-lib/src/common_fs.rs

@@ -5,6 +5,8 @@ use std::path::{Component, Path};
 use std::{fs, io};
 use std::{ops::RangeInclusive, path::PathBuf};
 
+use crate::cli::LinesChangedOnly;
+
 /// A structure to represent a file's path and line changes.
 #[derive(Debug)]
 pub struct FileObj {
@@ -52,7 +54,7 @@ impl FileObj {
     /// A helper function to consolidate a [Vec<u32>] of line numbers into a
     /// [Vec<RangeInclusive<u32>>] in which each range describes the beginning and
     /// ending of a group of consecutive line numbers.
-    fn consolidate_numbers_to_ranges(lines: &Vec<u32>) -> Vec<RangeInclusive<u32>> {
+    fn consolidate_numbers_to_ranges(lines: &[u32]) -> Vec<RangeInclusive<u32>> {
         let mut range_start = None;
         let mut ranges: Vec<RangeInclusive<u32>> = Vec::new();
         for (index, number) in lines.iter().enumerate() {
@@ -69,13 +71,11 @@ impl FileObj {
         ranges
     }
 
-    pub fn get_ranges(&self, lines_changed_only: u8) -> Vec<RangeInclusive<u32>> {
-        if lines_changed_only == 2 {
-            self.diff_chunks.to_vec()
-        } else if lines_changed_only == 1 {
-            self.added_ranges.to_vec()
-        } else {
-            Vec::new()
+    pub fn get_ranges(&self, lines_changed_only: &LinesChangedOnly) -> Vec<RangeInclusive<u32>> {
+        match lines_changed_only {
+            LinesChangedOnly::Diff => self.diff_chunks.to_vec(),
+            LinesChangedOnly::On => self.added_ranges.to_vec(),
+            _ => Vec::new(),
         }
     }
 }
@@ -249,6 +249,7 @@ mod test {
     use std::path::PathBuf;
 
     use super::{get_line_cols_from_offset, list_source_files, normalize_path, FileObj};
+    use crate::cli::LinesChangedOnly;
     use crate::cli::{get_arg_parser, parse_ignore};
     use crate::common_fs::is_file_in_list;
 
@@ -406,7 +407,7 @@ mod test {
     #[test]
     fn get_ranges_0() {
         let file_obj = FileObj::new(PathBuf::from("tests/demo/demo.cpp"));
-        let ranges = file_obj.get_ranges(0);
+        let ranges = file_obj.get_ranges(&LinesChangedOnly::Off);
         assert!(ranges.is_empty());
     }
 
@@ -419,7 +420,7 @@ mod test {
             added_lines,
             diff_chunks.clone(),
         );
-        let ranges = file_obj.get_ranges(2);
+        let ranges = file_obj.get_ranges(&LinesChangedOnly::Diff);
         assert_eq!(ranges, diff_chunks);
     }
 
@@ -432,7 +433,7 @@ mod test {
             added_lines,
             diff_chunks,
         );
-        let ranges = file_obj.get_ranges(1);
+        let ranges = file_obj.get_ranges(&LinesChangedOnly::On);
         assert_eq!(ranges, vec![4..=5, 9..=9]);
     }
 }

cpp-linter-lib/src/run.rs

@@ -13,7 +13,7 @@ use openssl_probe;
 
 // project specific modules/crates
 use crate::clang_tools::capture_clang_tools_output;
-use crate::cli::{convert_extra_arg_val, get_arg_parser, parse_ignore};
+use crate::cli::{convert_extra_arg_val, get_arg_parser, parse_ignore, LinesChangedOnly};
 use crate::common_fs::{list_source_files, FileObj};
 use crate::github_api::GithubApiClient;
 use crate::logger::{self, end_log_group, start_log_group};
@@ -90,15 +90,14 @@ pub fn run_main(args: Vec<String>) -> i32 {
         .unwrap()
         .as_str()
     {
-        "false" => 0,
-        "true" => 1,
-        "diff" => 2,
-        _ => unreachable!(),
+        "true" => LinesChangedOnly::On,
+        "diff" => LinesChangedOnly::Diff,
+        _ => LinesChangedOnly::Off,
     };
     let files_changed_only = args.get_flag("files-changed-only");
 
     start_log_group(String::from("Get list of specified source files"));
-    let files: Vec<FileObj> = if lines_changed_only != 0 || files_changed_only {
+    let files: Vec<FileObj> = if lines_changed_only != LinesChangedOnly::Off || files_changed_only {
         // parse_diff(github_rest_api_payload)
         rest_api_client.get_list_of_changed_files(&extensions, &ignored, &not_ignored)
     } else {
@@ -128,7 +127,7 @@ pub fn run_main(args: Vec<String>) -> i32 {
         args.get_one::<String>("version").unwrap(),
         args.get_one::<String>("tidy-checks").unwrap(),
         user_inputs.style.as_str(),
-        lines_changed_only,
+        &lines_changed_only,
         database_path,
         extra_args,
     );