Fixing the flag issue (#5447)

* Fixing the flag issue

* whoops, forgot the original point of the function

* Update deparse.rs

* Update deparse.rs

* Update deparse.rs

* maybe this might work

* fmt

* quotation marks works now due to a rigorous check for args.

* fmt and clippy

* kept the original escape_quote_string(), escaped " and \

* removed script.nu

* Added appropriate comments.

crates/nu-parser/src/deparse.rs

@@ -1,3 +1,6 @@
+use std::fs::File;
+use std::io::{BufRead, BufReader};
+
 pub fn escape_quote_string(input: &str) -> String {
     let mut output = String::with_capacity(input.len() + 2);
     output.push('"');
@@ -12,3 +15,95 @@ pub fn escape_quote_string(input: &str) -> String {
     output.push('"');
     output
 }
+
+fn looks_like_flag(input: &str) -> bool {
+    if !input.starts_with('-') {
+        false
+        // it does not start with  '-'
+    } else if !input.starts_with("--") {
+        if input.len() > 2
+            && input.chars().nth(2).expect("this should never trigger") != '='
+            && input.chars().nth(2).expect("this should never trigger") != ' '
+        {
+            false
+            // while it start with '-', it is not of the form '-x=y' or '-x y'
+        } else {
+            input.len() >= 2
+        }
+    } else {
+        input.len() > 2
+        // it is either a flag --x or a '--'
+    }
+}
+
+fn escape_quote_string_when_flags_are_unclear(input: &str) -> String {
+    // internal use only. When reading the file for flags goes wrong, revert back to a manual check
+    // for flags.
+    let mut output = String::new();
+    if !looks_like_flag(input) {
+        output.push('"');
+        for c in input.chars() {
+            if c == '"' || c == '\\' {
+                output.push('\\');
+            }
+            output.push(c);
+        }
+        output.push('"');
+        output
+    } else if input.contains(' ') || input.contains('=') {
+        // this is a flag that requires delicate handling
+        let mut flag_tripped = false;
+        for c in input.chars() {
+            if c == '"' || c == '\\' {
+                output.push('\\');
+            }
+            output.push(c);
+            if (c == ' ' || c == '=') && !flag_tripped {
+                flag_tripped = true;
+                output.push('"');
+            }
+        }
+        output.push('"');
+        output
+    } else {
+        // this is a normal flag, aka "--x"
+        String::from(input)
+    }
+}
+
+pub fn escape_quote_string_with_file(input: &str, file: &str) -> String {
+    // use when you want to cross-compare to a file to ensure flags are checked properly
+    let file = File::open(file);
+    match file {
+        Ok(f) => {
+            let lines = BufReader::new(f).lines();
+            for line in lines {
+                let mut flag_start = false;
+                let mut word = String::new();
+                let line_or = line.unwrap_or_else(|_| String::from(" "));
+                if line_or.contains('-') {
+                    for n in line_or.chars() {
+                        if n == '-' {
+                            flag_start = true;
+                        }
+                        if n == ' ' || n == ':' || n == ')' {
+                            flag_start = false;
+                        }
+                        if flag_start {
+                            word.push(n);
+                        }
+                    }
+                }
+                if word == input {
+                    return word;
+                }
+            }
+            let mut final_word = String::new();
+            final_word.push('"');
+            final_word.push_str(input);
+            final_word.push('"');
+            final_word
+        }
+        _ => escape_quote_string_when_flags_are_unclear(input),
+    }
+}

crates/nu-parser/src/lib.rs

@@ -8,7 +8,7 @@ mod parse_keywords;
 mod parser;
 mod type_check;
 
-pub use deparse::escape_quote_string;
+pub use deparse::{escape_quote_string, escape_quote_string_with_file};
 pub use errors::ParseError;
 pub use flatten::{flatten_block, flatten_expression, flatten_pipeline, FlatShape};
 pub use known_external::KnownExternal;

src/main.rs

@@ -17,7 +17,7 @@ use nu_cli::{
 };
 use nu_command::{create_default_context, BufferedReader};
 use nu_engine::{get_full_help, CallExt};
-use nu_parser::{escape_quote_string, parse};
+use nu_parser::{escape_quote_string, escape_quote_string_with_file, parse};
 use nu_protocol::{
     ast::{Call, Expr, Expression},
     engine::{Command, EngineState, Stack, StateWorkingSet},
@@ -82,7 +82,7 @@ fn main() -> Result<()> {
     let mut args = std::env::args().skip(1);
     while let Some(arg) = args.next() {
         if !script_name.is_empty() {
-            args_to_script.push(escape_quote_string(&arg));
+            args_to_script.push(escape_quote_string_with_file(&arg, &script_name));
         } else if arg.starts_with('-') {
             // Cool, it's a flag
             let flag_value = match arg.as_ref() {