Add a very silly table

crates/nu-command/src/default_context.rs

@@ -7,6 +7,7 @@ use nu_protocol::{
 
 use crate::{
     where_::Where, Alias, Benchmark, BuildString, Def, Do, Each, For, If, Length, Let, LetEnv, Ls,
+    Table,
 };
 
 pub fn create_default_context() -> Rc<RefCell<EngineState>> {
@@ -45,6 +46,8 @@ pub fn create_default_context() -> Rc<RefCell<EngineState>> {
 
         working_set.add_decl(Box::new(Ls));
 
+        working_set.add_decl(Box::new(Table));
+
         let sig = Signature::build("exit");
         working_set.add_decl(sig.predeclare());
         let sig = Signature::build("vars");

crates/nu-command/src/lib.rs

@@ -11,6 +11,7 @@ mod length;
 mod let_;
 mod let_env;
 mod ls;
+mod table;
 mod where_;
 
 pub use alias::Alias;
@@ -26,3 +27,4 @@ pub use length::Length;
 pub use let_::Let;
 pub use let_env::LetEnv;
 pub use ls::Ls;
+pub use table::Table;

crates/nu-command/src/table.rs

@@ -0,0 +1,125 @@
+use std::collections::HashMap;
+
+use nu_protocol::ast::{Call, PathMember};
+use nu_protocol::engine::{Command, EvaluationContext};
+use nu_protocol::{Signature, Span, Value};
+use nu_table::StyledString;
+
+pub struct Table;
+
+//NOTE: this is not a real implementation :D. It's just a simple one to test with until we port the real one.
+impl Command for Table {
+    fn name(&self) -> &str {
+        "table"
+    }
+
+    fn usage(&self) -> &str {
+        "Render the table."
+    }
+
+    fn signature(&self) -> nu_protocol::Signature {
+        Signature::build("table")
+    }
+
+    fn run(
+        &self,
+        _context: &EvaluationContext,
+        call: &Call,
+        input: Value,
+    ) -> Result<nu_protocol::Value, nu_protocol::ShellError> {
+        match input {
+            Value::List { vals, .. } => {
+                let table = convert_to_table(vals);
+
+                if let Some(table) = table {
+                    let result = nu_table::draw_table(&table, 80, &HashMap::new());
+
+                    Ok(Value::String {
+                        val: result,
+                        span: call.head,
+                    })
+                } else {
+                    Ok(Value::Nothing { span: call.head })
+                }
+            }
+            Value::Stream { stream, .. } => {
+                let table = convert_to_table(stream);
+
+                if let Some(table) = table {
+                    let result = nu_table::draw_table(&table, 80, &HashMap::new());
+
+                    Ok(Value::String {
+                        val: result,
+                        span: call.head,
+                    })
+                } else {
+                    Ok(Value::Nothing { span: call.head })
+                }
+            }
+            x => Ok(x),
+        }
+    }
+}
+
+fn convert_to_table(iter: impl IntoIterator<Item = Value>) -> Option<nu_table::Table> {
+    let mut iter = iter.into_iter().peekable();
+
+    if let Some(first) = iter.peek() {
+        let mut headers = first.columns();
+        headers.insert(0, "#".into());
+
+        let mut data = vec![];
+
+        for (row_num, item) in iter.enumerate() {
+            let mut row = vec![row_num.to_string()];
+
+            for header in headers.iter().skip(1) {
+                let result = item.clone().follow_cell_path(&[PathMember::String {
+                    val: header.into(),
+                    span: Span::unknown(),
+                }]);
+
+                match result {
+                    Ok(value) => row.push(value.into_string()),
+                    Err(_) => row.push(String::new()),
+                }
+            }
+
+            data.push(row);
+        }
+
+        Some(nu_table::Table {
+            headers: headers
+                .into_iter()
+                .map(|x| StyledString {
+                    contents: x,
+                    style: nu_table::TextStyle::default_header(),
+                })
+                .collect(),
+            data: data
+                .into_iter()
+                .map(|x| {
+                    x.into_iter()
+                        .enumerate()
+                        .map(|(col, y)| {
+                            if col == 0 {
+                                StyledString {
+                                    contents: y,
+                                    style: nu_table::TextStyle::default_header(),
+                                }
+                            } else {
+                                StyledString {
+                                    contents: y,
+                                    style: nu_table::TextStyle::basic_left(),
+                                }
+                            }
+                        })
+                        .collect::<Vec<StyledString>>()
+                })
+                .collect(),
+            theme: nu_table::Theme::rounded(),
+        })
+    } else {
+        None
+    }
+}