From b6ba7f97fd692d5fb2fe2e028425fa6aea560684 Mon Sep 17 00:00:00 2001
From: Jonathan Turner <jonathan.d.turner@gmail.com>
Date: Sun, 8 Dec 2019 18:58:53 +1300
Subject: [PATCH] WIP param completions

---
 crates/nu-parser/src/hir/syntax_shape.rs |  6 +-
 crates/nu-parser/src/lib.rs              |  4 +-
 src/cli.rs                               |  2 +-
 src/shell/completer.rs                   | 96 +++++++++++++++++++-----
 4 files changed, 83 insertions(+), 25 deletions(-)

diff --git a/crates/nu-parser/src/hir/syntax_shape.rs b/crates/nu-parser/src/hir/syntax_shape.rs
index 98483eb1ad..04d89e93aa 100644
--- a/crates/nu-parser/src/hir/syntax_shape.rs
+++ b/crates/nu-parser/src/hir/syntax_shape.rs
@@ -182,10 +182,10 @@ pub trait SignatureRegistry {
 #[derive(Getters, new)]
 pub struct ExpandContext<'context> {
     #[get = "pub(crate)"]
-    registry: Box<dyn SignatureRegistry>,
+    pub registry: Box<dyn SignatureRegistry>,
     #[get = "pub(crate)"]
-    source: &'context Text,
-    homedir: Option<PathBuf>,
+    pub source: &'context Text,
+    pub homedir: Option<PathBuf>,
 }
 
 impl<'context> ExpandContext<'context> {
diff --git a/crates/nu-parser/src/lib.rs b/crates/nu-parser/src/lib.rs
index 41c7cde5f5..05194a67eb 100644
--- a/crates/nu-parser/src/lib.rs
+++ b/crates/nu-parser/src/lib.rs
@@ -6,7 +6,9 @@ pub mod parse_command;
 pub use crate::commands::classified::{ClassifiedCommand, ClassifiedPipeline, InternalCommand};
 pub use crate::commands::ExternalCommand;
 pub use crate::hir::syntax_shape::flat_shape::FlatShape;
-pub use crate::hir::syntax_shape::{expand_syntax, ExpandSyntax, PipelineShape, SignatureRegistry};
+pub use crate::hir::syntax_shape::{
+    expand_syntax, ExpandContext, ExpandSyntax, PipelineShape, SignatureRegistry,
+};
 pub use crate::hir::tokens_iterator::TokensIterator;
 pub use crate::parse::files::Files;
 pub use crate::parse::flag::Flag;
diff --git a/src/cli.rs b/src/cli.rs
index dbfd8641d0..4e0bcfc0e3 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -587,7 +587,7 @@ async fn process_line(readline: Result<String, ReadlineError>, ctx: &mut Context
     }
 }
 
-fn classify_pipeline(
+pub fn classify_pipeline(
     pipeline: &TokenNode,
     context: &Context,
     source: &Text,
diff --git a/src/shell/completer.rs b/src/shell/completer.rs
index 27aeaed155..ca038f7236 100644
--- a/src/shell/completer.rs
+++ b/src/shell/completer.rs
@@ -16,28 +16,10 @@ impl NuCompleter {
         pos: usize,
         context: &rustyline::Context,
     ) -> rustyline::Result<(usize, Vec<rustyline::completion::Pair>)> {
+        use nu_source::{HasSpan, Text};
+
         let commands: Vec<String> = self.commands.names();
 
-        let mut completions = self.file_completer.complete(line, pos, context)?.1;
-
-        for completion in &mut completions {
-            if completion.replacement.contains("\\ ") {
-                completion.replacement = completion.replacement.replace("\\ ", " ");
-            }
-            if completion.replacement.contains("\\(") {
-                completion.replacement = completion.replacement.replace("\\(", "(");
-            }
-
-            if completion.replacement.contains(' ') || completion.replacement.contains('(') {
-                if !completion.replacement.starts_with('\"') {
-                    completion.replacement = format!("\"{}", completion.replacement);
-                }
-                if !completion.replacement.ends_with('\"') {
-                    completion.replacement = format!("{}\"", completion.replacement);
-                }
-            }
-        }
-
         let line_chars: Vec<_> = line[..pos].chars().collect();
         let mut replace_pos = line_chars.len();
         while replace_pos > 0 {
@@ -47,6 +29,80 @@ impl NuCompleter {
             replace_pos -= 1;
         }
 
+        // See if we're a flag
+        let mut completions = vec![];
+
+        if pos > 0 && line_chars[pos - 1] == '-' {
+            let mut line_copy = line.to_string();
+            let replace_string = (replace_pos..pos).map(|_| " ").collect::<String>();
+            line_copy.replace_range(replace_pos..pos, &replace_string);
+            match nu_parser::parse(&line_copy) {
+                Ok(val) => {
+                    let source = Text::from(line);
+                    let pipeline_list = vec![val.clone()];
+                    let mut iterator =
+                        nu_parser::TokensIterator::all(&pipeline_list, source.clone(), val.span());
+
+                    let expand_context = nu_parser::ExpandContext {
+                        homedir: None,
+                        registry: Box::new(self.commands.clone()),
+                        source: &source,
+                    };
+
+                    let result = nu_parser::expand_syntax(
+                        &nu_parser::PipelineShape,
+                        &mut iterator,
+                        &expand_context,
+                    );
+
+                    if let Ok(result) = result {
+                        for command in result.commands.list {
+                            match command {
+                                nu_parser::ClassifiedCommand::Internal(
+                                    nu_parser::InternalCommand { args, .. },
+                                ) => {
+                                    if replace_pos >= args.span.start()
+                                        && replace_pos <= args.span.end()
+                                    {
+                                        if let Some(named) = args.named {
+                                            for (name, _) in named.iter() {
+                                                completions.push(rustyline::completion::Pair {
+                                                    display: format!("--{}", name),
+                                                    replacement: format!("--{}", name),
+                                                });
+                                            }
+                                        }
+                                    }
+                                }
+                                _ => {}
+                            }
+                        }
+                    }
+                }
+                _ => {}
+            }
+        } else {
+            completions = self.file_completer.complete(line, pos, context)?.1;
+
+            for completion in &mut completions {
+                if completion.replacement.contains("\\ ") {
+                    completion.replacement = completion.replacement.replace("\\ ", " ");
+                }
+                if completion.replacement.contains("\\(") {
+                    completion.replacement = completion.replacement.replace("\\(", "(");
+                }
+
+                if completion.replacement.contains(' ') || completion.replacement.contains('(') {
+                    if !completion.replacement.starts_with('\"') {
+                        completion.replacement = format!("\"{}", completion.replacement);
+                    }
+                    if !completion.replacement.ends_with('\"') {
+                        completion.replacement = format!("{}\"", completion.replacement);
+                    }
+                }
+            }
+        };
+
         for command in commands.iter() {
             let mut pos = replace_pos;
             let mut matched = true;