From e365f22084c67c7b9bd4e91713b577d4d0450b9f Mon Sep 17 00:00:00 2001
From: Mattias Wadman <mattias.wadman@gmail.com>
Date: Wed, 5 Jan 2022 21:36:22 +0100
Subject: [PATCH] interp: Cleanup stdio usage and functions

---
 doc/usage.md           |  1 +
 pkg/interp/assert.jq   |  6 +++---
 pkg/interp/decode.jq   |  5 ++---
 pkg/interp/funcs.jq    |  4 ++--
 pkg/interp/internal.jq | 16 +++++++++++-----
 pkg/interp/interp.go   |  6 +++---
 pkg/interp/interp.jq   | 13 ++++++-------
 pkg/interp/options.jq  | 14 +++++++++-----
 8 files changed, 37 insertions(+), 28 deletions(-)

diff --git a/doc/usage.md b/doc/usage.md
index 955ff6373..5eaf96660 100644
--- a/doc/usage.md
+++ b/doc/usage.md
@@ -260,6 +260,7 @@ notable is support for arbitrary-precision integers.
 
 - All standard library functions from jq
 - Adds a few new general functions:
+  - `print/0`, `println/0`, `printerr/0`, `printerrln` prints to stdout and stderr.
   - `streaks/0`, `streaks_by/1` like `group` but groups streaks based on condition.
   - `count/0`, `count_by/1` like `group` but counts groups lengths.
   - `debug/1` like `debug/0` but uses arg to produce debug message. `{a: 123} | debug({a}) | ...`.
diff --git a/pkg/interp/assert.jq b/pkg/interp/assert.jq
index 00bd21a72..acdbf9f6f 100644
--- a/pkg/interp/assert.jq
+++ b/pkg/interp/assert.jq
@@ -1,10 +1,10 @@
-def log: if env.VERBOSE then stderr else empty end;
+def log: if env.VERBOSE then printerrln else empty end;
 
 def assert($name; $expected; $actual):
   ( if $expected == $actual then
-      "PASS \($name)\n" | log
+      "PASS \($name)" | log
     else
-      ( "FAIL \($name): expected \($expected) got \($actual)\n" | stderr
+      ( "FAIL \($name): expected \($expected) got \($actual)" | printerrln
       , (null | halt_error(1))
       )
     end
diff --git a/pkg/interp/decode.jq b/pkg/interp/decode.jq
index 7b3cc0ddb..6856b84f2 100644
--- a/pkg/interp/decode.jq
+++ b/pkg/interp/decode.jq
@@ -25,18 +25,17 @@ def _decode_progress:
       )
     else empty
     end
-  | stderr
+  | printerr
   );
 
 def decode($name; $decode_opts):
   ( options as $opts
-  | (null | stdout) as $stdout
   | _decode(
       $name;
       $opts +
       {
         _progress: (
-          if $opts.decode_progress and $opts.repl and $stdout.is_terminal then
+          if $opts.decode_progress and $opts.repl and stdout_tty.is_terminal then
             "_decode_progress"
           else null
           end
diff --git a/pkg/interp/funcs.jq b/pkg/interp/funcs.jq
index c56b90179..ecc32068b 100644
--- a/pkg/interp/funcs.jq
+++ b/pkg/interp/funcs.jq
@@ -2,11 +2,11 @@ def display($opts):
   ( options($opts) as $opts
   | if _can_display then _display($opts)
     else
-      ( if type == "string" and $opts.raw_string then (tostring | stdout)
+      ( if type == "string" and $opts.raw_string then print
         else _print_color_json($opts)
         end
       , ( $opts.join_string
-        | if . then stdout else empty end
+        | if . then print else empty end
         )
       )
     end
diff --git a/pkg/interp/internal.jq b/pkg/interp/internal.jq
index c4bf5c91f..46399fb67 100644
--- a/pkg/interp/internal.jq
+++ b/pkg/interp/internal.jq
@@ -1,9 +1,16 @@
 # is here to be defined as early as possible to allow debugging
-# TODO: move to builtin.jq etc?
-def print: stdout;
-def println: ., "\n" | stdout;
+# TODO: move some _* to builtin.jq etc?
+
+def stdin_tty: null | _stdin;
+def stdout_tty: null | _stdout;
+
+def print: tostring | _stdout;
+def println: ., "\n" | print;
+def printerr: tostring | _stderr;
+def printerrln: ., "\n" | printerr;
+
 def debug:
-  ( ((["DEBUG", .] | tojson), "\n" | stderr)
+  ( ((["DEBUG", .] | tojson) | printerrln)
   , .
   );
 def debug(f): . as $c | f | debug | $c;
@@ -118,4 +125,3 @@ def _is_scalar:
 def _is_context_canceled_error: . == "context canceled";
 
 def _error_str: "error: \(.)";
-def _errorln: ., "\n" | stderr;
diff --git a/pkg/interp/interp.go b/pkg/interp/interp.go
index ab0fbca72..11531b299 100644
--- a/pkg/interp/interp.go
+++ b/pkg/interp/interp.go
@@ -54,9 +54,9 @@ func init() {
 		return []Function{
 			{"_readline", 0, 2, i.readline, nil},
 			{"eval", 1, 2, nil, i.eval},
-			{"stdin", 0, 0, nil, i.makeStdioFn(i.os.Stdin())},
-			{"stdout", 0, 0, nil, i.makeStdioFn(i.os.Stdout())},
-			{"stderr", 0, 0, nil, i.makeStdioFn(i.os.Stderr())},
+			{"_stdin", 0, 0, nil, i.makeStdioFn(i.os.Stdin())},
+			{"_stdout", 0, 0, nil, i.makeStdioFn(i.os.Stdout())},
+			{"_stderr", 0, 0, nil, i.makeStdioFn(i.os.Stderr())},
 			{"_extkeys", 0, 0, i._extKeys, nil},
 			{"_exttype", 0, 0, i._extType, nil},
 			{"_global_state", 0, 1, i.makeStateFn(i.state), nil},
diff --git a/pkg/interp/interp.jq b/pkg/interp/interp.jq
index 1302a0ad6..7e9fa58a0 100644
--- a/pkg/interp/interp.jq
+++ b/pkg/interp/interp.jq
@@ -58,7 +58,7 @@ def input:
         ( . as $err
         | _input_io_errors(. += {($h): $err}) as $_
         | $err
-        | (_error_str | _errorln)
+        | (_error_str | printerrln)
         , _input($opts; f)
         )
     | try f
@@ -71,7 +71,7 @@ def input:
             else ": failed to decode (try -d FORMAT)"
             end
           ] | join("")
-        | (_error_str | _errorln)
+        | (_error_str | printerrln)
         , _input($opts; f)
         )
     );
@@ -143,7 +143,7 @@ def var($k): . as $c | var($k; $c);
 def _cli_expr_on_error:
   ( . as $err
   | _cli_last_expr_error($err) as $_
-  | (_error_str | _errorln)
+  | (_error_str | printerrln)
   );
 def _cli_expr_on_compile_error:
   ( _eval_compile_error_tostring
@@ -180,7 +180,6 @@ def _main:
   def _usage($arg0):
     "Usage: \($arg0) [OPTIONS] [--] [EXPR] [FILE...]";
   ( . as {$version, $args, args: [$arg0]}
-  | (null | [stdin, stdout]) as [$stdin, $stdout]
   # make sure we don't unintentionally use . to make things clearer
   | null
   | ( try _args_parse($args[1:]; _opt_cli_opts)
@@ -311,10 +310,10 @@ def _main:
         $opts.null_input == false and
         ($opts.repl | not) and
         ($opts.expr_file | not) and
-        $stdin.is_terminal and
-        $stdout.is_terminal
+        stdin_tty.is_terminal and
+        stdout_tty.is_terminal
       ) then
-      ( (( _usage($arg0), "\n") | stderr)
+      ( (_usage($arg0) | printerrln)
       , null | halt_error(_exit_code_args_error)
       )
     else
diff --git a/pkg/interp/options.jq b/pkg/interp/options.jq
index 48cc7ee1f..40a0a418a 100644
--- a/pkg/interp/options.jq
+++ b/pkg/interp/options.jq
@@ -2,7 +2,7 @@ def _obj_to_csv_kv:
   [to_entries[] | [.key, .value] | join("=")] | join(",");
 
 def _opt_build_default_fixed:
-  ( (null | stdout) as $stdout
+  ( stdout_tty as $stdout
   | {
       addrbase:       16,
       arg:            [],
@@ -55,11 +55,15 @@ def _opt_build_default_fixed:
   );
 
 def _opt_default_dynamic:
-  ( (null | stdout) as $stdout
+  ( stdout_tty as $stdout
+  # TODO: intdiv 2 * 2 to get even number, nice or maybe not needed?
+  | ( if $stdout.is_terminal then [_intdiv(_intdiv($stdout.width; 8); 2) * 2, 4] | max
+      else 16
+      end
+    ) as $display_bytes
   | {
-      # TODO: intdiv 2 * 2 to get even number, nice or maybe not needed?
-      display_bytes:   (if $stdout.is_terminal then [_intdiv(_intdiv($stdout.width; 8); 2) * 2, 4] | max else 16 end),
-      line_bytes:      (if $stdout.is_terminal then [_intdiv(_intdiv($stdout.width; 8); 2) * 2, 4] | max else 16 end),
+      display_bytes: $display_bytes,
+      line_bytes: $display_bytes,
     }
   );