rust: start improving errors reporting.

- refactor error![] macro, switch place for $msg & $ok parameters.
- add more meaningful NcError return values in several functions related with poc-menu example, for starters.
- the poc-menu example now doesn't randomly fail, IDKW but OK I guess.
- minor unrelated corrections.

rust/examples/full-basics.rs

@@ -3,7 +3,6 @@ use libnotcurses_sys::*;
 fn main() -> NcResult<()> {
     let nc = Notcurses::new()?;
     let stdplane = nc.stdplane()?;
-    let p1 = NcPlane::new(nc, 0, 0, 20, 30);
 
     for ch in "Initializing cells...".chars() {
         let cell = NcCell::with_char7b(ch);

rust/src/cells/methods.rs

@@ -76,7 +76,7 @@ impl NcCell {
         channels: NcChannelPair,
     ) -> NcResult<u32> {
         let bytes = crate::cell_prime(plane, cell, gcluster, style, channels);
-        error![bytes, bytes as u32]
+        error![bytes, "", bytes as u32]
     }
 
     /// Duplicate this NcCell into another one.

rust/src/direct/methods.rs

@@ -71,7 +71,6 @@ impl NcDirect {
     pub fn raster_frame(&mut self, faken: &mut NcPlane, align: NcAlign) -> NcResult<()> {
         error![
             unsafe { crate::ncdirect_raster_frame(self, faken, align) },
-            (),
             "Rastering frame"
         ]
     }
@@ -311,6 +310,7 @@ impl NcDirect {
         let (mut y, mut x) = (0, 0);
         error![
             unsafe { crate::ncdirect_cursor_yx(self, &mut y, &mut x) },
+            "",
             (y as NcDimension, x as NcDimension)
         ]
     }

rust/src/macros.rs

@@ -119,18 +119,18 @@ macro_rules! printf {
 /// type `()`, and an empty `&str` `""`, respectively.
 #[macro_export]
 macro_rules! error {
-    ($res:expr, $ok:expr, $msg:expr) => {
+    ($res:expr, $msg:expr, $ok:expr) => {
         if $res >= crate::NCRESULT_OK {
             return Ok($ok);
         } else {
             return Err(crate::NcError::with_msg($res, $msg));
         }
     };
-    ($res:expr, $ok:expr) => {
-        error![$res, $ok, ""];
+    ($res:expr, $msg:expr) => {
+        error![$res, $msg, ()];
     };
     ($res:expr) => {
-        error![$res, (), ""];
+        error![$res, "", ()];
     };
 }
 

rust/src/notcurses/methods.rs

@@ -113,7 +113,7 @@ impl Notcurses {
     /// Returns a Notcurses context, expects [NotcursesOptions].
     pub fn with_options<'a>(options: NotcursesOptions) -> NcResult<&'a mut Notcurses> {
         let res = unsafe { notcurses_init(&options, null_mut()) };
-        error_ref_mut![res, "Initializing Notcurses"]
+        error_ref_mut![res, "Notcurses.with_options()"]
     }
 
     /// Returns a Notcurses context. Expects [NcLogLevel] and flags.
@@ -355,7 +355,7 @@ impl Notcurses {
         let mut blitter = 0;
         error![
             unsafe { crate::notcurses_lex_blitter(cstring![op], &mut blitter) },
-            blitter, "Invalid blitter name"
+            "Invalid blitter name", blitter
         ]
     }
 
@@ -376,7 +376,7 @@ impl Notcurses {
         let mut scalemode = 0;
         error![
             unsafe { crate::notcurses_lex_scalemode(cstring![op], &mut scalemode) },
-            scalemode
+            "", scalemode
         ]
     }
 
@@ -412,7 +412,10 @@ impl Notcurses {
     ///
     /// *C style function: [notcurses_mouse_enable()][crate::notcurses_mouse_enable].*
     pub fn mouse_enable(&mut self) -> NcResult<()> {
-        error![unsafe { crate::notcurses_mouse_enable(self) }]
+        error![
+            unsafe { crate::notcurses_mouse_enable(self) },
+            "Notcurses.mouse_enable()"
+        ]
     }
 
     /// Returns the number of simultaneous colors claimed to be supported,
@@ -440,6 +443,7 @@ impl Notcurses {
         let (mut y, mut x) = (0, 0);
         error![
             unsafe { crate::notcurses_refresh(self, &mut y, &mut x) },
+            "",
             (y as NcDimension, x as NcDimension)
         ]
     }
@@ -448,7 +452,10 @@ impl Notcurses {
     ///
     /// *C style function: [notcurses_render()][crate::notcurses_render].*
     pub fn render(&mut self) -> NcResult<()> {
-        error![unsafe { crate::notcurses_render(self) }]
+        error![
+            unsafe { crate::notcurses_render(self) },
+            "Notcurses.render()"
+        ]
     }
 
     /// Performs the rendering and rasterization portion of
@@ -540,7 +547,10 @@ impl Notcurses {
     ///
     /// *C style function: [notcurses_stdplane()][crate::notcurses_stdplane].*
     pub fn stdplane<'a>(&mut self) -> NcResult<&'a mut NcPlane> {
-        error_ref_mut![unsafe { crate::notcurses_stdplane(self) }]
+        error_ref_mut![
+            unsafe { crate::notcurses_stdplane(self) },
+            "Notcurses.stdplane()"
+        ]
     }
 
     /// Returns a reference to the standard [NcPlane] for this terminal.

rust/src/plane/methods.rs

@@ -248,7 +248,7 @@ impl NcPlane {
     ) -> NcResult<NcDimension> {
         let res =
             unsafe { crate::ncplane_stain(self, y_stop as i32, x_stop as i32, ul, ur, ll, lr) };
-        error![res, res as NcDimension];
+        error![res, "", res as NcDimension];
     }
 }
 
@@ -410,7 +410,7 @@ impl NcPlane {
     ) -> NcResult<NcDimension> {
         let res =
             unsafe { crate::ncplane_format(self, y_stop as i32, x_stop as i32, stylemask as u32) };
-        error![res, res as NcDimension]
+        error![res, "", res as NcDimension]
     }
 
     /// Returns the current styling for this NcPlane.
@@ -503,7 +503,7 @@ impl NcPlane {
     #[inline]
     pub fn at_cursor_cell(&mut self, cell: &mut NcCell) -> NcResult<u32> {
         let bytes = unsafe { crate::ncplane_at_cursor_cell(self, cell) };
-        error![bytes, bytes as u32]
+        error![bytes, "", bytes as u32]
     }
 
     /// Retrieves the current contents of the specified [NcCell], returning the
@@ -541,7 +541,7 @@ impl NcPlane {
         cell: &mut NcCell,
     ) -> NcResult<u32> {
         let bytes = unsafe { crate::ncplane_at_yx_cell(self, y as i32, x as i32, cell) };
-        error![bytes, bytes as u32]
+        error![bytes, "", bytes as u32]
     }
 
     /// Extracts this NcPlane's base [NcCell] into `cell`.
@@ -570,7 +570,10 @@ impl NcPlane {
         stylemask: NcStyleMask,
         channels: NcChannelPair,
     ) -> NcResult<()> {
-        error![unsafe { crate::ncplane_set_base(self, &(egc as i8), stylemask as u32, channels) }]
+        error![
+            unsafe { crate::ncplane_set_base(self, &(egc as i8), stylemask as u32, channels) },
+            &format!("NcPlane.set_base({}, {}, {})", egc, stylemask, channels)
+        ]
     }
 
     /// Sets this NcPlane's base NcCell.
@@ -650,7 +653,7 @@ impl NcPlane {
         cell: &NcCell,
     ) -> NcResult<NcDimension> {
         let res = unsafe { crate::ncplane_putc_yx(self, y as i32, x as i32, cell) };
-        error![res, res as NcDimension]
+        error![res, "", res as NcDimension]
     }
 
     /// Replaces the NcCell at the current coordinates with the provided NcCell,
@@ -662,7 +665,7 @@ impl NcPlane {
     /// *C style function: [ncplane_putc()][crate::ncplane_putc].*
     pub fn putc(&mut self, cell: &NcCell) -> NcResult<NcDimension> {
         let res = crate::ncplane_putc(self, cell);
-        error![res, res as NcDimension]
+        error![res, "", res as NcDimension]
     }
 
     /// Calls [putchar_yx][NcPlane#method.putchar_yx] at the current cursor location.
@@ -672,7 +675,7 @@ impl NcPlane {
     /// *C style function: [ncplane_putchar()][crate::ncplane_putchar].*
     pub fn putchar(&mut self, ch: char) -> NcResult<NcDimension> {
         let res = crate::ncplane_putchar(self, ch);
-        error![res, res as NcDimension]
+        error![res, "", res as NcDimension]
     }
 
     // TODO: call put_egc
@@ -696,7 +699,7 @@ impl NcPlane {
         ch: char,
     ) -> NcResult<NcDimension> {
         let res = crate::ncplane_putchar_yx(self, y, x, ch);
-        error![res, res as NcDimension]
+        error![res, "", res as NcDimension]
     }
 
     /// Writes a series of [NcEgc][crate::NcEgc]s to the current location,
@@ -712,7 +715,7 @@ impl NcPlane {
     #[inline]
     pub fn putstr(&mut self, string: &str) -> NcResult<NcDimension> {
         let res = crate::ncplane_putstr(self, string);
-        error![res, res as NcDimension]
+        error![res, "", res as NcDimension]
     }
 
     /// Same as [putstr][NcPlane#method.putstr], but it also tries to move the
@@ -742,7 +745,11 @@ impl NcPlane {
         string: &str,
     ) -> NcResult<NcDimension> {
         let res = unsafe { crate::ncplane_putstr_aligned(self, y as i32, align, cstring![string]) };
-        error![res, res as NcDimension]
+        error![
+            res,
+            &format!("NcPlane.putstr_aligned({}, {}, {})", y, align, string),
+            res as NcDimension
+        ]
     }
 
     /// Writes a series of [NcEgc][crate::NcEgc]s to the current location, but
@@ -758,7 +765,7 @@ impl NcPlane {
     /// *C style function: [ncplane_putstr_stained()][crate::ncplane_putstr_stained].*
     pub fn putstr_stained(&mut self, string: &str) -> NcResult<NcDimension> {
         let res = unsafe { crate::ncplane_putstr_stained(self, cstring![string]) };
-        error![res, res as NcDimension]
+        error![res, "", res as NcDimension]
     }
 
     /// Write a string, which is a series of [NcEgc][crate::NcEgc]s, to the
@@ -780,7 +787,7 @@ impl NcPlane {
         string: &str,
     ) -> NcResult<NcDimension> {
         let res = unsafe { crate::ncplane_putstr_yx(self, y as i32, x as i32, cstring![string]) };
-        error![res, res as NcDimension]
+        error![res, "", res as NcDimension]
     }
 }
 
@@ -1625,7 +1632,7 @@ impl NcPlane {
                 x_stop as i32,
             )
         };
-        error![res, res as NcDimension]
+        error![res, "", res as NcDimension]
     }
 
     /// Draw a gradient with its upper-left corner at the current cursor position,
@@ -1647,7 +1654,7 @@ impl NcPlane {
         x_len: NcDimension,
     ) -> NcResult<NcDimension> {
         let res = crate::ncplane_gradient_sized(self, egc, stylemask, ul, ur, ll, lr, y_len, x_len);
-        error![res, res as NcDimension]
+        error![res, "", res as NcDimension]
     }
 
     /// Draws a high-resolution gradient using upper blocks and synced backgrounds.
@@ -1671,7 +1678,7 @@ impl NcPlane {
         let res = unsafe {
             crate::ncplane_highgradient(self, ul, ur, ll, lr, y_stop as i32, x_stop as i32)
         };
-        error![res, res as NcDimension]
+        error![res, "", res as NcDimension]
     }
 
     /// [`gradient_sized`][NcPlane#method.gradient_sized]
@@ -1690,7 +1697,7 @@ impl NcPlane {
         let res = unsafe {
             crate::ncplane_highgradient_sized(self, ul, ur, ll, lr, y_stop as i32, x_stop as i32)
         };
-        error![res, res as NcDimension]
+        error![res, "", res as NcDimension]
     }
 
     /// Converts this NcPlane's content to greyscale.

rust/src/widgets/menu/methods/menu.rs

@@ -32,9 +32,15 @@ impl NcMenu {
     ///
     /// *C style function: [ncmenu_item_set_status()][crate::ncmenu_item_set_status].*
     pub fn item_set_status(&mut self, section: &str, item: &str, enabled: bool) -> NcResult<()> {
-        error![unsafe {
-            crate::ncmenu_item_set_status(self, cstring![section], cstring![item], enabled)
-        }]
+        error![
+            unsafe {
+                crate::ncmenu_item_set_status(self, cstring![section], cstring![item], enabled)
+            },
+            &format!(
+                ".item_set_status({:?}, {:?}, {:?}, {})",
+                self, section, item, enabled
+            )
+        ]
     }
 
     /// Returns the [NcMenuItem][crate::NcMenuItem] description