Add more input/output type annotations (#7532)

crates/nu-command/src/system/complete.rs

@@ -1,7 +1,7 @@
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, Value,
+    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, Type, Value,
 };
 
 #[derive(Clone)]
@@ -13,7 +13,9 @@ impl Command for Complete {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("complete").category(Category::System)
+        Signature::build("complete")
+            .category(Category::System)
+            .input_output_types(vec![(Type::Any, Type::Record(vec![]))])
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/system/exec.rs

@@ -3,7 +3,7 @@ use nu_engine::{current_dir, env_to_strings, CallExt};
 use nu_protocol::{
     ast::{Call, Expr},
     engine::{Command, EngineState, Stack},
-    Category, Example, PipelineData, ShellError, Signature, Spanned, SyntaxShape,
+    Category, Example, PipelineData, ShellError, Signature, Spanned, SyntaxShape, Type,
 };
 use std::os::unix::process::CommandExt;
 
@@ -17,6 +17,7 @@ impl Command for Exec {
 
     fn signature(&self) -> Signature {
         Signature::build("exec")
+            .input_output_types(vec![(Type::Nothing, Type::Any)])
             .required("command", SyntaxShape::String, "the command to execute")
             .rest(
                 "rest",

crates/nu-command/src/system/nu_check.rs

@@ -3,7 +3,7 @@ use nu_parser::{parse, parse_module_block, unescape_unquote_string};
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack, StateWorkingSet};
 use nu_protocol::{
-    Category, Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Value,
+    Category, Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
 };
 
 #[derive(Clone)]
@@ -16,6 +16,9 @@ impl Command for NuCheck {
 
     fn signature(&self) -> Signature {
         Signature::build("nu-check")
+            .input_output_types(vec![(Type::String, Type::Bool),
+            (Type::ListStream, Type::Bool),
+            (Type::List(Box::new(Type::Any)), Type::Bool)])
             // type is string to avoid automatically canonicalizing the path
             .optional("path", SyntaxShape::String, "File path to parse")
             .switch("as-module", "Parse content as module", Some('m'))

crates/nu-command/src/system/ps.rs

@@ -3,7 +3,8 @@ use std::time::Duration;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    Category, Example, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Value,
+    Category, Example, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Type,
+    Value,
 };
 
 #[derive(Clone)]
@@ -16,6 +17,7 @@ impl Command for Ps {
 
     fn signature(&self) -> Signature {
         Signature::build("ps")
+            .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
             .switch(
                 "long",
                 "list all available columns for each entry",

crates/nu-command/src/system/registry_query.rs

@@ -3,7 +3,7 @@ use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
     Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, ShellError,
-    Signature, Span, Spanned, SyntaxShape, Value,
+    Signature, Span, Spanned, SyntaxShape, Type, Value,
 };
 use winreg::{enums::*, RegKey};
 
@@ -31,6 +31,7 @@ impl Command for RegistryQuery {
 
     fn signature(&self) -> Signature {
         Signature::build("registry query")
+            .input_output_types(vec![(Type::Nothing, Type::Any)])
             .switch("hkcr", "query the hkey_classes_root hive", None)
             .switch("hkcu", "query the hkey_current_user hive", None)
             .switch("hklm", "query the hkey_local_machine hive", None)

crates/nu-command/src/system/run_external.rs

@@ -2,11 +2,13 @@ use fancy_regex::Regex;
 use itertools::Itertools;
 use nu_engine::env_to_strings;
 use nu_engine::CallExt;
-use nu_protocol::ast::{Expr, Expression};
-use nu_protocol::did_you_mean;
-use nu_protocol::engine::{EngineState, Stack};
-use nu_protocol::{ast::Call, engine::Command, ShellError, Signature, SyntaxShape, Value};
-use nu_protocol::{Category, Example, ListStream, PipelineData, RawStream, Span, Spanned};
+use nu_protocol::{
+    ast::{Call, Expr, Expression},
+    did_you_mean,
+    engine::{Command, EngineState, Stack},
+    Category, Example, ListStream, PipelineData, RawStream, ShellError, Signature, Span, Spanned,
+    SyntaxShape, Type, Value,
+};
 use nu_system::ForegroundProcess;
 use pathdiff::diff_paths;
 use std::collections::HashMap;
@@ -34,6 +36,7 @@ impl Command for External {
 
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build(self.name())
+            .input_output_types(vec![(Type::Any, Type::Any)])
             .switch("redirect-stdout", "redirect stdout to the pipeline", None)
             .switch("redirect-stderr", "redirect stderr to the pipeline", None)
             .switch("trim-end-newline", "trimming end newlines", None)

crates/nu-command/src/system/sys.rs

@@ -3,7 +3,7 @@ use chrono::Local;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, Value,
+    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, Type, Value,
 };
 use std::time::{Duration, UNIX_EPOCH};
 use sysinfo::{ComponentExt, CpuExt, DiskExt, NetworkExt, System, SystemExt, UserExt};
@@ -17,7 +17,10 @@ impl Command for Sys {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("sys").filter().category(Category::System)
+        Signature::build("sys")
+            .filter()
+            .category(Category::System)
+            .input_output_types(vec![(Type::Nothing, Type::Record(vec![]))])
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/system/which_.rs

@@ -6,7 +6,7 @@ use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
     Category, Example, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Span,
-    Spanned, SyntaxShape, Value,
+    Spanned, SyntaxShape, Type, Value,
 };
 
 use std::ffi::OsStr;
@@ -22,6 +22,8 @@ impl Command for Which {
 
     fn signature(&self) -> Signature {
         Signature::build("which")
+            .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
+            .allow_variants_without_examples(true)
             .required("application", SyntaxShape::String, "application")
             .rest("rest", SyntaxShape::String, "additional applications")
             .switch("all", "list all executables", Some('a'))