Split format_table into separate crate and reduce k2v-client dependencies

src/format-table/lib.rs

@@ -0,0 +1,49 @@
+//! Format tables with a stupid API.
+//!
+//! Example:
+//!
+//! ```rust
+//! let mut table = vec!["product\tquantity\tprice".to_string()];
+//! for (p, q, r) in [("tomato", 12, 15), ("potato", 10, 20), ("rice", 5, 12)] {
+//! 	table.push(format!("{}\t{}\t{}", p, q, r));
+//! }
+//! format_table::format_table(table);
+//! ```
+//!
+//! A table to be formatted is a `Vec<String>`, containing one string per line.
+//! Table columns in each line are separated by a `\t` character.
+
+/// Format a table and return the result as a string.
+pub fn format_table_to_string(data: Vec<String>) -> String {
+	let data = data
+		.iter()
+		.map(|s| s.split('\t').collect::<Vec<_>>())
+		.collect::<Vec<_>>();
+
+	let columns = data.iter().map(|row| row.len()).fold(0, std::cmp::max);
+	let mut column_size = vec![0; columns];
+
+	let mut out = String::new();
+
+	for row in data.iter() {
+		for (i, col) in row.iter().enumerate() {
+			column_size[i] = std::cmp::max(column_size[i], col.chars().count());
+		}
+	}
+
+	for row in data.iter() {
+		for (col, col_len) in row[..row.len() - 1].iter().zip(column_size.iter()) {
+			out.push_str(col);
+			(0..col_len - col.chars().count() + 2).for_each(|_| out.push(' '));
+		}
+		out.push_str(row[row.len() - 1]);
+		out.push('\n');
+	}
+
+	out
+}
+
+/// Format a table and print the result to stdout.
+pub fn format_table(data: Vec<String>) {
+	print!("{}", format_table_to_string(data));
+}