Category option for signature (#343)

* category option for signature

* category option for signature

* column description for $scope

crates/nu-command/src/formats/from/command.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, ShellError, Signature};
+use nu_protocol::{Category, PipelineData, ShellError, Signature};
 
 #[derive(Clone)]
 pub struct From;
@@ -15,7 +15,7 @@ impl Command for From {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("from")
+        Signature::build("from").category(Category::Formats)
     }
 
     fn run(

crates/nu-command/src/formats/from/csv.rs

@@ -3,7 +3,7 @@ use super::delimited::from_delimited_data;
 use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, SyntaxShape, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, SyntaxShape, Value};
 
 #[derive(Clone)]
 pub struct FromCsv;
@@ -26,6 +26,7 @@ impl Command for FromCsv {
                 "don't treat the first row as column names",
                 Some('n'),
             )
+            .category(Category::Formats)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/formats/from/eml.rs

@@ -4,6 +4,7 @@ use indexmap::map::IndexMap;
 use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
+use nu_protocol::Category;
 use nu_protocol::Config;
 use nu_protocol::{
     Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Value,
@@ -20,12 +21,14 @@ impl Command for FromEml {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from eml").named(
-            "preview-body",
-            SyntaxShape::Int,
-            "How many bytes of the body to preview",
-            Some('b'),
-        )
+        Signature::build("from eml")
+            .named(
+                "preview-body",
+                SyntaxShape::Int,
+                "How many bytes of the body to preview",
+                Some('b'),
+            )
+            .category(Category::Formats)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/formats/from/json.rs

@@ -1,8 +1,8 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, ShellError, Signature,
-    Span, Value,
+    Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, ShellError,
+    Signature, Span, Value,
 };
 
 #[derive(Clone)]
@@ -18,11 +18,9 @@ impl Command for FromJson {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("from json").switch(
-            "objects",
-            "treat each line as a separate value",
-            Some('o'),
-        )
+        Signature::build("from json")
+            .switch("objects", "treat each line as a separate value", Some('o'))
+            .category(Category::Formats)
     }
 
     fn examples(&self) -> Vec<Example> {

crates/nu-command/src/formats/from/tsv.rs

@@ -2,7 +2,7 @@ use super::delimited::from_delimited_data;
 
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Config, PipelineData, ShellError, Signature};
+use nu_protocol::{Category, Config, PipelineData, ShellError, Signature};
 
 #[derive(Clone)]
 pub struct FromTsv;
@@ -13,11 +13,13 @@ impl Command for FromTsv {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from csv").switch(
-            "noheaders",
-            "don't treat the first row as column names",
-            Some('n'),
-        )
+        Signature::build("from csv")
+            .switch(
+                "noheaders",
+                "don't treat the first row as column names",
+                Some('n'),
+            )
+            .category(Category::Formats)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/formats/from/url.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Config, Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Config, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct FromUrl;
@@ -11,7 +11,7 @@ impl Command for FromUrl {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from url")
+        Signature::build("from url").category(Category::Formats)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/formats/from/yaml.rs

@@ -2,7 +2,8 @@ use itertools::Itertools;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Config, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, Spanned, Value,
+    Category, Config, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span,
+    Spanned, Value,
 };
 use serde::de::Deserialize;
 use std::collections::HashMap;
@@ -16,7 +17,7 @@ impl Command for FromYaml {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from yaml")
+        Signature::build("from yaml").category(Category::Formats)
     }
 
     fn usage(&self) -> &str {
@@ -84,7 +85,7 @@ impl Command for FromYml {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from yml")
+        Signature::build("from yml").category(Category::Formats)
     }
 
     fn usage(&self) -> &str {