Add descriptions to arguments

src/commands/cd.rs

@@ -10,7 +10,11 @@ impl WholeStreamCommand for CD {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("cd").optional("directory", SyntaxShape::Path)
+        Signature::build("cd").optional(
+            "directory",
+            SyntaxShape::Path,
+            "the directory to change to",
+        )
     }
 
     fn usage(&self) -> &str {

src/commands/config.rs

@@ -26,12 +26,16 @@ impl WholeStreamCommand for Config {
 
     fn signature(&self) -> Signature {
         Signature::build("config")
-            .named("load", SyntaxShape::Path)
-            .named("set", SyntaxShape::Any)
-            .named("get", SyntaxShape::Any)
-            .named("remove", SyntaxShape::Any)
-            .switch("clear")
-            .switch("path")
+            .named(
+                "load",
+                SyntaxShape::Path,
+                "load the config from the path give",
+            )
+            .named("set", SyntaxShape::Any, "set a value in the config")
+            .named("get", SyntaxShape::Any, "get a value from the config")
+            .named("remove", SyntaxShape::Any, "remove a value from the config")
+            .switch("clear", "clear the config")
+            .switch("path", "return the path to the config file")
     }
 
     fn usage(&self) -> &str {

src/commands/cp.rs

@@ -21,10 +21,9 @@ impl PerItemCommand for Cpy {
 
     fn signature(&self) -> Signature {
         Signature::build("cp")
-            .required("src", SyntaxShape::Pattern)
-            .required("dst", SyntaxShape::Path)
-            .named("file", SyntaxShape::Any)
-            .switch("recursive")
+            .required("src", SyntaxShape::Pattern, "the place to copy from")
+            .required("dst", SyntaxShape::Path, "the place to copy to")
+            .switch("recursive", "copy recursively through subdirectories")
     }
 
     fn usage(&self) -> &str {

src/commands/date.rs

@@ -17,7 +17,9 @@ impl WholeStreamCommand for Date {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("date").switch("utc").switch("local")
+        Signature::build("date")
+            .switch("utc", "use universal time (UTC)")
+            .switch("local", "use the local time")
     }
 
     fn usage(&self) -> &str {

src/commands/echo.rs

@@ -12,7 +12,7 @@ impl PerItemCommand for Echo {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("echo").rest(SyntaxShape::Any)
+        Signature::build("echo").rest(SyntaxShape::Any, "the values to echo")
     }
 
     fn usage(&self) -> &str {

src/commands/enter.rs

@@ -14,7 +14,11 @@ impl PerItemCommand for Enter {
     }
 
     fn signature(&self) -> registry::Signature {
-        Signature::build("enter").required("location", SyntaxShape::Path)
+        Signature::build("enter").required(
+            "location",
+            SyntaxShape::Path,
+            "the location to create a new shell from",
+        )
     }
 
     fn usage(&self) -> &str {

src/commands/exit.rs

@@ -11,7 +11,7 @@ impl WholeStreamCommand for Exit {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("exit").switch("now")
+        Signature::build("exit").switch("now", "exit out of the shell immediately")
     }
 
     fn usage(&self) -> &str {

src/commands/fetch.rs

@@ -19,8 +19,12 @@ impl PerItemCommand for Fetch {
 
     fn signature(&self) -> Signature {
         Signature::build(self.name())
-            .required("path", SyntaxShape::Path)
-            .switch("raw")
+            .required(
+                "path",
+                SyntaxShape::Path,
+                "the URL to fetch the contents from",
+            )
+            .switch("raw", "fetch contents as text rather than a table")
     }
 
     fn usage(&self) -> &str {

src/commands/first.rs

@@ -16,7 +16,11 @@ impl WholeStreamCommand for First {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("first").optional("rows", SyntaxShape::Int)
+        Signature::build("first").optional(
+            "rows",
+            SyntaxShape::Int,
+            "starting from the front, the number of rows to return",
+        )
     }
 
     fn usage(&self) -> &str {

src/commands/from_csv.rs

@@ -16,7 +16,8 @@ impl WholeStreamCommand for FromCSV {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from-csv").switch("headerless")
+        Signature::build("from-csv")
+            .switch("headerless", "don't treat the first row as column names")
     }
 
     fn usage(&self) -> &str {

src/commands/from_json.rs

@@ -15,7 +15,7 @@ impl WholeStreamCommand for FromJSON {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from-json").switch("objects")
+        Signature::build("from-json").switch("objects", "treat each line as a separate value")
     }
 
     fn usage(&self) -> &str {

src/commands/from_ssv.rs

@@ -21,8 +21,12 @@ impl WholeStreamCommand for FromSSV {
 
     fn signature(&self) -> Signature {
         Signature::build(STRING_REPRESENTATION)
-            .switch("headerless")
-            .named("minimum-spaces", SyntaxShape::Int)
+            .switch("headerless", "don't treat the first row as column names")
+            .named(
+                "minimum-spaces",
+                SyntaxShape::Int,
+                "the mininum spaces to separate columns",
+            )
     }
 
     fn usage(&self) -> &str {

src/commands/from_tsv.rs

@@ -16,7 +16,8 @@ impl WholeStreamCommand for FromTSV {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from-tsv").switch("headerless")
+        Signature::build("from-tsv")
+            .switch("headerless", "don't treat the first row as column names")
     }
 
     fn usage(&self) -> &str {

src/commands/get.rs

@@ -20,8 +20,15 @@ impl WholeStreamCommand for Get {
 
     fn signature(&self) -> Signature {
         Signature::build("get")
-            .required("member", SyntaxShape::ColumnPath)
-            .rest(SyntaxShape::ColumnPath)
+            .required(
+                "member",
+                SyntaxShape::ColumnPath,
+                "the path to the data to get",
+            )
+            .rest(
+                SyntaxShape::ColumnPath,
+                "optionally return additional data by path",
+            )
     }
 
     fn usage(&self) -> &str {

src/commands/group_by.rs

@@ -16,7 +16,11 @@ impl WholeStreamCommand for GroupBy {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("group-by").required("column_name", SyntaxShape::String)
+        Signature::build("group-by").required(
+            "column_name",
+            SyntaxShape::String,
+            "the name of the column to group by",
+        )
     }
 
     fn usage(&self) -> &str {

src/commands/help.rs

@@ -12,7 +12,7 @@ impl PerItemCommand for Help {
     }
 
     fn signature(&self) -> registry::Signature {
-        Signature::build("help").rest(SyntaxShape::Any)
+        Signature::build("help").rest(SyntaxShape::Any, "the name of command(s) to get help on")
     }
 
     fn usage(&self) -> &str {
@@ -65,8 +65,8 @@ impl PerItemCommand for Help {
                             one_liner.push_str("{flags} ");
                         }
 
-                        for positional in signature.positional {
-                            match positional {
+                        for positional in &signature.positional {
+                            match &positional.0 {
                                 PositionalType::Mandatory(name, _m) => {
                                     one_liner.push_str(&format!("<{}> ", name));
                                 }
@@ -77,25 +77,66 @@ impl PerItemCommand for Help {
                         }
 
                         if signature.rest_positional.is_some() {
-                            one_liner.push_str(" ...args");
+                            one_liner.push_str(&format!(" ...args",));
                         }
+
                         long_desc.push_str(&format!("\nUsage:\n  > {}\n", one_liner));
 
+                        if signature.positional.len() > 0 || signature.rest_positional.is_some() {
+                            long_desc.push_str("\nparameters:\n");
+                            for positional in signature.positional {
+                                match positional.0 {
+                                    PositionalType::Mandatory(name, _m) => {
+                                        long_desc
+                                            .push_str(&format!("  <{}> {}\n", name, positional.1));
+                                    }
+                                    PositionalType::Optional(name, _o) => {
+                                        long_desc
+                                            .push_str(&format!("  ({}) {}\n", name, positional.1));
+                                    }
+                                }
+                            }
+                            if signature.rest_positional.is_some() {
+                                long_desc.push_str(&format!(
+                                    "  ...args{} {}\n",
+                                    if signature.rest_positional.is_some() {
+                                        ":"
+                                    } else {
+                                        ""
+                                    },
+                                    signature.rest_positional.unwrap().1
+                                ));
+                            }
+                        }
                         if signature.named.len() > 0 {
                             long_desc.push_str("\nflags:\n");
                             for (flag, ty) in signature.named {
-                                match ty {
+                                match ty.0 {
                                     NamedType::Switch => {
-                                        long_desc.push_str(&format!("  --{}\n", flag));
+                                        long_desc.push_str(&format!(
+                                            "  --{}{} {}\n",
+                                            flag,
+                                            if ty.1.len() > 0 { ":" } else { "" },
+                                            ty.1
+                                        ));
                                     }
                                     NamedType::Mandatory(m) => {
                                         long_desc.push_str(&format!(
-                                            "  --{} <{}> (required parameter)\n",
-                                            flag, m
+                                            "  --{} <{}> (required parameter){} {}\n",
+                                            flag,
+                                            m,
+                                            if ty.1.len() > 0 { ":" } else { "" },
+                                            ty.1
                                         ));
                                     }
                                     NamedType::Optional(o) => {
-                                        long_desc.push_str(&format!("  --{} <{}>\n", flag, o));
+                                        long_desc.push_str(&format!(
+                                            "  --{} <{}>{} {}\n",
+                                            flag,
+                                            o,
+                                            if ty.1.len() > 0 { ":" } else { "" },
+                                            ty.1
+                                        ));
                                     }
                                 }
                             }

src/commands/last.rs

@@ -16,7 +16,11 @@ impl WholeStreamCommand for Last {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("last").optional("rows", SyntaxShape::Number)
+        Signature::build("last").optional(
+            "rows",
+            SyntaxShape::Number,
+            "starting from the back, the number of rows to return",
+        )
     }
 
     fn usage(&self) -> &str {

src/commands/ls.rs

@@ -16,7 +16,11 @@ impl WholeStreamCommand for LS {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("ls").optional("path", SyntaxShape::Pattern)
+        Signature::build("ls").optional(
+            "path",
+            SyntaxShape::Pattern,
+            "a path to get the directory contents from",
+        )
     }
 
     fn usage(&self) -> &str {

src/commands/mkdir.rs

@@ -17,7 +17,7 @@ impl PerItemCommand for Mkdir {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("mkdir").rest(SyntaxShape::Path)
+        Signature::build("mkdir").rest(SyntaxShape::Path, "the name(s) of the path(s) to create")
     }
 
     fn usage(&self) -> &str {

src/commands/mv.rs

@@ -20,9 +20,16 @@ impl PerItemCommand for Move {
 
     fn signature(&self) -> Signature {
         Signature::build("mv")
-            .required("source", SyntaxShape::Pattern)
-            .required("destination", SyntaxShape::Path)
-            .named("file", SyntaxShape::Any)
+            .required(
+                "source",
+                SyntaxShape::Pattern,
+                "the location to move files/directories from",
+            )
+            .required(
+                "destination",
+                SyntaxShape::Path,
+                "the location to move files/directories to",
+            )
     }
 
     fn usage(&self) -> &str {

src/commands/nth.rs

@@ -16,7 +16,11 @@ impl WholeStreamCommand for Nth {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("nth").required("row number", SyntaxShape::Any)
+        Signature::build("nth").required(
+            "row number",
+            SyntaxShape::Any,
+            "the number of the row to return",
+        )
     }
 
     fn usage(&self) -> &str {

src/commands/open.rs

@@ -16,8 +16,12 @@ impl PerItemCommand for Open {
 
     fn signature(&self) -> Signature {
         Signature::build(self.name())
-            .required("path", SyntaxShape::Path)
-            .switch("raw")
+            .required(
+                "path",
+                SyntaxShape::Path,
+                "the file path to load values from",
+            )
+            .switch("raw", "load content as a string insead of a table")
     }
 
     fn usage(&self) -> &str {

src/commands/pick.rs

@@ -17,7 +17,7 @@ impl WholeStreamCommand for Pick {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("pick").rest(SyntaxShape::Any)
+        Signature::build("pick").rest(SyntaxShape::Any, "the columns to select from the table")
     }
 
     fn usage(&self) -> &str {

src/commands/pivot.rs

@@ -21,9 +21,12 @@ impl WholeStreamCommand for Pivot {
 
     fn signature(&self) -> Signature {
         Signature::build("pivot")
-            .switch("header-row")
-            .switch("ignore-titles")
-            .rest(SyntaxShape::String)
+            .switch("header-row", "treat the first row as column names")
+            .switch("ignore-titles", "don't pivot the column names into values")
+            .rest(
+                SyntaxShape::String,
+                "the names to give columns once pivoted",
+            )
     }
 
     fn usage(&self) -> &str {