jc: add completions and README (#1144)

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Errors:

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Author: RGBCube

modules/jc/README.md

@@ -0,0 +1,34 @@
+# jc (JSON converter)
+
+jc converts the output of many commands, file-types, and strings to JSON or YAML
+
+This module provides a wrapper around the `jc` command line tool and
+automatically parses its output into a structured data format.
+
+## Example
+
+```nu
+> df | jc --df
+
+┌─#─┬───filesystem───┬─1k_blocks─┬───used────┬─available─┬─────────mounted_on─────────┬─use_percent─┬─capacity_percent─┐
+│ 0 │ /dev/disk3s1s1 │ 482797652 │ 368026060 │ 114771592 │ /                          │          77 │               24 │
+│ 1 │ /dev/disk3s6   │ 482797652 │ 368026060 │ 114771592 │ /System/Volumes/VM         │          77 │               24 │
+│ 2 │ /dev/disk3s2   │ 482797652 │ 368026060 │ 114771592 │ /System/Volumes/Preboot    │          77 │               24 │
+│ 3 │ /dev/disk3s4   │ 482797652 │ 368026060 │ 114771592 │ /System/Volumes/Update     │          77 │               24 │
+│ 4 │ /dev/disk1s2   │    512000 │     23052 │    488948 │ /System/Volumes/xarts      │           5 │               96 │
+│ 5 │ /dev/disk1s1   │    512000 │     23052 │    488948 │ /System/Volumes/iSCPreboot │           5 │               96 │
+│ 6 │ /dev/disk1s3   │    512000 │     23052 │    488948 │ /System/Volumes/Hardware   │           5 │               96 │
+│ 7 │ /dev/disk3s7   │ 482797652 │ 368026060 │ 114771592 │ /nix                       │          77 │               24 │
+│ 8 │ /dev/disk4     │    524288 │     12316 │    511972 │ /private/var/run/agenix.d  │           3 │               98 │
+└───┴────────────────┴───────────┴───────────┴───────────┴────────────────────────────┴─────────────┴──────────────────┘
+```
+
+## Installation
+
+1. Install the `jc` command line:
+   <https://kellyjonbrazil.github.io/jc/#installation>
+
+2. Source this module in your `config.nu`:
+   ```nu
+   use modules/jc
+   ```

modules/jc/mod.nu

@@ -1,28 +1,79 @@
-# Run `jc` (Json Converter)
-#
-# This module provides a wrapper around the `jc` command line tool and automatically
-# parses its output into a structured data format.
-#
-# Dependencies:
-#     * `jc`
-#
-# Installation:
-#     1. Install the `jc` command line: https://kellyjonbrazil.github.io/jc/#installation
-#     2. Import this module in your `config.nu`: `import ~/.local/share/nu_scripts/modules/jc/`
-export def --wrapped main [...args]: [any -> table, any -> record, any -> string] {
-  let run = (^jc ...$args | complete)
+def --env "nu-complete jc" [commandline: string] {
+  let stor = stor open
+
+  if $stor.jc_completions? == null {
+    stor create --table-name jc_completions --columns { value: str, description: str, is_flag: bool }
+  }
+
+  if $stor.jc_completions_ran? == null {
+    stor create --table-name jc_completions_ran --columns { _: bool }
+  }
+
+  if $stor.jc_completions_ran == [] { try {
+    let about = ^jc --about
+    | from json
+
+    let magic = $about
+    | get parsers
+    | each { { value: $in.magic_commands?, description: $in.description } }
+    | where value != null
+    | flatten
+
+    let options = $about
+    | get parsers
+    | select argument description
+    | rename value description
+
+    let inherent = ^jc --help
+    | lines
+    | split list "" # Group with empty lines as boundary.
+    | where { $in.0? == "Options:" } | get 0 # Get the first section that starts with "Options:"
+    | skip 1 # Remove header
+    | each { str trim }
+    | parse "{short},  {long} {description}"
+    | update description { str trim }
+    | each {|record|
+      [[value, description];
+        [$record.short, $record.description],
+        [$record.long, $record.description],
+      ]
+    }
+    | flatten
+
+    for entry in $magic {
+      stor insert --table-name jc_completions --data-record ($entry | insert is_flag false)
+    }
+
+    for entry in ($options ++ $inherent) {
+      stor insert --table-name jc_completions --data-record ($entry | insert is_flag true)
+    }
+
+    stor insert --table-name jc_completions_ran --data-record { _: true }
+  } }
+
+  if ($commandline | str contains "-") {
+    $stor.jc_completions
+  } else {
+    $stor.jc_completions
+    | where is_flag == 0
+  } | select value description
+}
+
+# Run `jc` (JSON Converter).
+export def --wrapped main [...arguments: string@"nu-complete jc"]: [any -> table, any -> record, any -> string] {
+  let run = ^jc ...$arguments | complete
 
   if $run.exit_code != 0 {
     error make {
-      msg: $run.stderr,
+      msg: "jc exection failed"
       label: {
-        text: "jc execution failed",
-        span: (metadata $args).span
+        text: ($run.stderr | str replace "jc:" "" | str replace "Error -" "" | str trim)
+        span: (metadata $arguments).span
       }
     }
   }
 
-  if '--help' in $args or '-h' in $args {
+  if "--help" in $arguments or "-h" in $arguments {
     $run.stdout
   } else {
     $run.stdout | from json