added help --find to search usage and extra_usage text for strings (#…

…3948)

* added help --find to search usage and extra_usage text for strings

* changed my mind

crates/nu-command/src/commands/core_commands/help.rs

@@ -1,14 +1,12 @@
 use crate::prelude::*;
 use crate::TaggedListBuilder;
-use nu_engine::documentation::generate_docs;
-use nu_engine::{Command, WholeStreamCommand};
+use nu_engine::{documentation::generate_docs, Command, WholeStreamCommand};
 use nu_errors::ShellError;
 use nu_protocol::{
- NamedType, PositionalType, ReturnSuccess, Signature, SyntaxShape, TaggedDictBuilder,
- UntaggedValue, Value,
+ Dictionary, NamedType, PositionalType, ReturnSuccess, Signature, SyntaxShape,
+ TaggedDictBuilder, UntaggedValue, Value,
 };
-use nu_source::Tag;
-use nu_source::{SpannedItem, Tagged};
+use nu_source::{SpannedItem, Tag, Tagged};
 use nu_value_ext::ValueExt;
 
 pub struct Help;
@@ -19,7 +17,14 @@ impl WholeStreamCommand for Help {
  }
 
  fn signature(&self) -> Signature {
- Signature::build("help").rest(SyntaxShape::String, "the name of command to get help on")
+ Signature::build("help")
+ .rest(SyntaxShape::String, "the name of command to get help on")
+ .named(
+ "find",
+ SyntaxShape::String,
+ "string to find in command usage",
+ Some('f'),
+ )
  }
 
  fn usage(&self) -> &str {
@@ -29,14 +34,81 @@ impl WholeStreamCommand for Help {
  fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
  help(args)
  }
+
+ fn examples(&self) -> Vec<Example> {
+ vec![
+ Example {
+ description: "show all commands and sub-commands",
+ example: "help commands",
+ result: None,
+ },
+ Example {
+ description: "generate documentation",
+ example: "help generate_docs",
+ result: None,
+ },
+ Example {
+ description: "show help for single command",
+ example: "help match",
+ result: None,
+ },
+ Example {
+ description: "show help for single sub-command",
+ example: "help str lpad",
+ result: None,
+ },
+ Example {
+ description: "search for string in command usage",
+ example: "help --find char",
+ result: None,
+ },
+ ]
+ }
 }
 
 fn help(args: CommandArgs) -> Result<ActionStream, ShellError> {
  let name = args.call_info.name_tag.clone();
  let scope = args.scope().clone();
-
+ let find: Option<Tagged<String>> = args.get_flag("find")?;
  let rest: Vec<Tagged<String>> = args.rest(0)?;
 
+ if let Some(f) = find {
+ let search_string = f.item;
+ let full_commands = scope.get_commands_info();
+ let mut found_cmds_vec = Vec::new();
+
+ for (key, cmd) in full_commands {
+ let mut indexmap = IndexMap::new();
+
+ let c = cmd.usage().to_string();
+ let e = cmd.extra_usage().to_string();
+ if key.to_lowercase().contains(&search_string)
+ || c.to_lowercase().contains(&search_string)
+ || e.to_lowercase().contains(&search_string)
+ {
+ indexmap.insert(
+ "name".to_string(),
+ UntaggedValue::string(key).into_value(&name),
+ );
+
+ indexmap.insert(
+ "usage".to_string(),
+ UntaggedValue::string(cmd.usage().to_string()).into_value(&name),
+ );
+
+ indexmap.insert(
+ "extra_usage".to_string(),
+ UntaggedValue::string(cmd.extra_usage().to_string()).into_value(&name),
+ );
+
+ found_cmds_vec
+ .push(UntaggedValue::Row(Dictionary::from(indexmap)).into_value(&name));
+ }
+ }
+
+ return Ok(found_cmds_vec.into_iter().into_action_stream());
+ }
+
  if !rest.is_empty() {
  if rest[0].item == "commands" {
  let mut sorted_names = scope.get_command_names();