use anyhow::{Context, Result};
use std::fs;
#[cfg(test)]
mod tests {
use super::merge_yaml_strings;
fn trim_start_lines(s: &str) -> String {
s.lines()
.map(|l| l.trim_start())
.collect::<Vec<&str>>()
.join("\n")
}
#[test]
fn yaml_merges_arrays() {
let yaml_a = r#"
list:
- a
"#;
let yaml_b = r#"
list:
- b
"#;
let result = merge_yaml_strings(&vec![yaml_a.to_string(), yaml_b.to_string()]).unwrap();
let expected = r#"{
"list": [
"a",
"b"
]
}"#;
assert_eq!(trim_start_lines(&expected), trim_start_lines(&result));
}
#[test]
fn yaml_merges_dictionaries() {
let yaml_a = r#"
dict:
a: true
"#;
let yaml_b = r#"
dict:
b: true
"#;
let result = merge_yaml_strings(&vec![yaml_a.to_string(), yaml_b.to_string()]).unwrap();
let expected = r#"{
"dict": {
"a": true,
"b": true
}
}"#;
assert_eq!(trim_start_lines(&expected), trim_start_lines(&result));
}
#[test]
fn yaml_merges_deeply() {
let yaml_a = r#"
dict:
list:
- a
"#;
let yaml_b = r#"
dict:
list:
- b
"#;
let result = merge_yaml_strings(&vec![yaml_a.to_string(), yaml_b.to_string()]).unwrap();
let expected = r#"{
"dict": {
"list": [
"a",
"b"
]
}
}"#;
assert_eq!(trim_start_lines(&expected), trim_start_lines(&result));
}
}
pub fn merge_yaml_strings(inputs: &Vec<String>) -> Result<String> {
let mut result: serde_json::Value = serde_json::from_str("{}")?;
for i in inputs {
let i: serde_json::Value =
serde_yaml::from_str(&i).with_context(|| format!("Failed to parse file {}", i))?;
result = merge_struct::merge(&result, &i)?;
}
return serde_json::to_string_pretty(&result)
.with_context(|| "converting json to pretty string");
}
pub fn merge_yaml_files(inputs: &Vec<String>, output: &str) -> Result<()> {
eprintln!("Will read from:");
for i in inputs {
eprintln!("- {}", i);
}
eprintln!("And write to: {}", output);
let mut input_contents = Vec::new();
for i in inputs {
let contents =
fs::read_to_string(i).with_context(|| format!("Failed to read file {}", i))?;
input_contents.push(contents);
}
let result = merge_yaml_strings(inputs).with_context(|| format!("Failed to merge yaml"))?;
fs::write(output, result).with_context(|| format!("Failed to write to {}", output))?;
return Ok(());
}