make FooterMode::Auto work (#14063)

# Description

@Yethal discovered that `FooterMode::Auto` in the config as
`$env.config.footer_mode = auto` did not work. This PR attempts to fix
that problem by implementing the auto algorithm that was already
supposed to work.

# User-Facing Changes
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# Tests + Formatting
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Cargo.lock

@@ -3493,6 +3493,7 @@ dependencies = [
  "nu-utils",
  "once_cell",
  "tabled",
+ "terminal_size",
 ]
 
 [[package]]

crates/nu-protocol/src/config/table.rs

@@ -63,7 +63,7 @@ pub enum FooterMode {
     Always,
     /// Only show the footer if there are more than RowCount rows
     RowCount(u64),
-    /// Calculate the screen height, calculate row count, if display will be bigger than screen, add the footer
+    /// Calculate the screen height and row count, if screen height is larger than row count, don't show footer
     Auto,
 }
 

crates/nu-table/Cargo.toml

@@ -22,6 +22,7 @@ nu-ansi-term = { workspace = true }
 once_cell = { workspace = true }
 fancy-regex = { workspace = true }
 tabled = { workspace = true, features = ["ansi"], default-features = false }
+terminal_size = { workspace = true }
 
 [dev-dependencies]
 # nu-test-support = { path="../nu-test-support", version = "0.98.1"  }

crates/nu-table/src/common.rs

@@ -3,6 +3,7 @@ use crate::{
 };
 use nu_color_config::{Alignment, StyleComputer, TextStyle};
 use nu_protocol::{Config, FooterMode, ShellError, Span, TableMode, TrimStrategy, Value};
+use terminal_size::{terminal_size, Height, Width};
 
 pub type NuText = (String, TextStyle);
 pub type TableResult = Result<Option<TableOutput>, ShellError>;
@@ -194,6 +195,21 @@ fn with_footer(config: &Config, with_header: bool, count_records: usize) -> bool
 }
 
 fn need_footer(config: &Config, count_records: u64) -> bool {
-    matches!(config.footer_mode, FooterMode::RowCount(limit) if count_records > limit)
-        || matches!(config.footer_mode, FooterMode::Always)
+    match config.footer_mode {
+        // Only show the footer if there are more than RowCount rows
+        FooterMode::RowCount(limit) => count_records > limit,
+        // Always show the footer
+        FooterMode::Always => true,
+        // Never show the footer
+        FooterMode::Never => false,
+        // Calculate the screen height and row count, if screen height is larger than row count, don't show footer
+        FooterMode::Auto => {
+            let (_width, height) = match terminal_size() {
+                Some((w, h)) => (Width(w.0).0 as u64, Height(h.0).0 as u64),
+                None => (Width(0).0 as u64, Height(0).0 as u64),
+            };
+
+            height <= count_records
+        }
+    }
 }