Move repl loop and command/script execution to nu_cli (#4846)

* Refactor usage of is_perf_true to be a parameter passed around

* Move repl loop and command/script execution to nu_cli

* Move config setup out of nu_cli

* Update config_files.rs

* Update main.rs

Co-authored-by: JT <547158+jntrnr@users.noreply.github.com>

crates/nu-cli/src/eval_file.rs

@@ -0,0 +1,145 @@
+use crate::util::{eval_source, report_error};
+use log::info;
+use log::trace;
+use miette::{IntoDiagnostic, Result};
+use nu_engine::convert_env_values;
+use nu_parser::parse;
+use nu_protocol::{
+    ast::Call,
+    engine::{EngineState, Stack, StateWorkingSet},
+    Config, PipelineData, Span, Value,
+};
+use std::io::Write;
+
+/// Main function used when a file path is found as argument for nu
+pub fn evaluate_file(
+    path: String,
+    args: &[String],
+    engine_state: &mut EngineState,
+    stack: &mut Stack,
+    input: PipelineData,
+    is_perf_true: bool,
+) -> Result<()> {
+    // Translate environment variables from Strings to Values
+    if let Some(e) = convert_env_values(engine_state, stack) {
+        let working_set = StateWorkingSet::new(engine_state);
+        report_error(&working_set, &e);
+        std::process::exit(1);
+    }
+
+    // Make a note of the exceptions we see for externals that look like math expressions
+    let exceptions = crate::util::external_exceptions(engine_state, stack);
+    engine_state.external_exceptions = exceptions;
+
+    let file = std::fs::read(&path).into_diagnostic()?;
+
+    let mut working_set = StateWorkingSet::new(engine_state);
+    trace!("parsing file: {}", path);
+
+    let _ = parse(&mut working_set, Some(&path), &file, false);
+
+    if working_set.find_decl(b"main").is_some() {
+        let args = format!("main {}", args.join(" "));
+
+        if !eval_source(
+            engine_state,
+            stack,
+            &file,
+            &path,
+            PipelineData::new(Span::new(0, 0)),
+        ) {
+            std::process::exit(1);
+        }
+        if !eval_source(engine_state, stack, args.as_bytes(), "<commandline>", input) {
+            std::process::exit(1);
+        }
+    } else if !eval_source(engine_state, stack, &file, &path, input) {
+        std::process::exit(1);
+    }
+
+    if is_perf_true {
+        info!("evaluate {}:{}:{}", file!(), line!(), column!());
+    }
+
+    Ok(())
+}
+
+pub fn print_table_or_error(
+    engine_state: &EngineState,
+    stack: &mut Stack,
+    mut pipeline_data: PipelineData,
+    config: &Config,
+) {
+    let exit_code = match &mut pipeline_data {
+        PipelineData::ExternalStream { exit_code, .. } => exit_code.take(),
+        _ => None,
+    };
+
+    match engine_state.find_decl("table".as_bytes()) {
+        Some(decl_id) => {
+            let table = engine_state.get_decl(decl_id).run(
+                engine_state,
+                stack,
+                &Call::new(Span::new(0, 0)),
+                pipeline_data,
+            );
+
+            match table {
+                Ok(table) => {
+                    for item in table {
+                        let stdout = std::io::stdout();
+
+                        if let Value::Error { error } = item {
+                            let working_set = StateWorkingSet::new(engine_state);
+
+                            report_error(&working_set, &error);
+
+                            std::process::exit(1);
+                        }
+
+                        let mut out = item.into_string("\n", config);
+                        out.push('\n');
+
+                        match stdout.lock().write_all(out.as_bytes()) {
+                            Ok(_) => (),
+                            Err(err) => eprintln!("{}", err),
+                        };
+                    }
+                }
+                Err(error) => {
+                    let working_set = StateWorkingSet::new(engine_state);
+
+                    report_error(&working_set, &error);
+
+                    std::process::exit(1);
+                }
+            }
+        }
+        None => {
+            for item in pipeline_data {
+                let stdout = std::io::stdout();
+
+                if let Value::Error { error } = item {
+                    let working_set = StateWorkingSet::new(engine_state);
+
+                    report_error(&working_set, &error);
+
+                    std::process::exit(1);
+                }
+
+                let mut out = item.into_string("\n", config);
+                out.push('\n');
+
+                match stdout.lock().write_all(out.as_bytes()) {
+                    Ok(_) => (),
+                    Err(err) => eprintln!("{}", err),
+                };
+            }
+        }
+    };
+
+    // Make sure everything has finished
+    if let Some(exit_code) = exit_code {
+        let _: Vec<_> = exit_code.into_iter().collect();
+    }
+}