improve diff check

crates/db_schema/src/schema_setup/diff_check.rs

@@ -22,7 +22,7 @@ pub fn get_dump(conn: &mut PgConnection) -> String {
     .expect("pg_export_snapshot failed");
   let snapshot_arg = format!("--snapshot={snapshot}");*/
   let output = Command::new("pg_dump")
-    .args(["--schema-only"])
+    .args(["--schema-only", "--no-owner", "--no-privileges", "--no-comments", "--no-publications", "--no-security-labels", "--no-subscriptions", "--no-table-access-method", "--no-tablespaces"])
     .env("DATABASE_URL", SETTINGS.get_database_url())
     .stderr(Stdio::inherit())
     .output()
@@ -45,6 +45,8 @@ pub fn check_dump_diff(conn: &mut PgConnection, mut before: String, name: &str)
   // Ignore timestamp differences by removing timestamps
   for dump in [&mut before, &mut after] {
     for index in 0.. {
+      let Some(byte)=dump.as_bytes().get(index) else{break};
+      if !byte.is_ascii_digit() {continue;}
       // Check for this pattern: 0000-00-00 00:00:00
       let Some((
         &[a0, a1, a2, a3, b0, a4, a5, b1, a6, a7, b2, a8, a9, b3, a10, a11, b4, a12, a13],
@@ -52,16 +54,16 @@ pub fn check_dump_diff(conn: &mut PgConnection, mut before: String, name: &str)
       )) = dump
         .get(index..)
         .and_then(|s| s.as_bytes().split_first_chunk::<PATTERN_LEN>())
-      else {
-        break;
+        else {
+          break;
       };
       if [a0, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13]
-        .into_iter()
-        .all(|byte| byte.is_ascii_digit())
+      .into_iter()
+      .all(|byte| byte.is_ascii_digit())
         && [b0, b1, b2, b3, b4] == *b"-- ::"
-      {
-        // Replace the part of the string that has the checked pattern and an optional fractional part
-        let len_after = if let Some((b'.', s)) = remaining.split_first() {
+        {
+          // Replace the part of the string that has the checked pattern and an optional fractional part
+          let len_after = if let Some((b'.', s)) = remaining.split_first() {
           1 + s.iter().position(|c| !c.is_ascii_digit()).unwrap_or(0)
         } else {
           0
@@ -77,12 +79,14 @@ pub fn check_dump_diff(conn: &mut PgConnection, mut before: String, name: &str)
   }
 
   let [before_chunks, after_chunks] =
-    [&before, &after].map(|dump| chunks(dump).collect::<BTreeSet<_>>());
-
+  [&before, &after].map(|dump| chunks(dump).collect::<BTreeSet<_>>());
+  let only_b = before_chunks.difference(&after_chunks).copied().map(process_chunk).collect::<BTreeSet<_>>();
+  let only_a = after_chunks.difference(&before_chunks).copied().map(process_chunk).collect::<BTreeSet<_>>();
+  
   // todo dont collect only_in_before?
   let [mut only_in_before, mut only_in_after] = [
-    before_chunks.difference(&after_chunks),
-    after_chunks.difference(&before_chunks),
+    only_b.difference(&only_a),
+    only_a.difference(&only_b),
   ]
   .map(|chunks| {
     chunks
@@ -121,12 +125,15 @@ pub fn check_dump_diff(conn: &mut PgConnection, mut before: String, name: &str)
       .iter()
       .enumerate()
       .max_by_key(|(_, (after_chunk, after_chunk_filtered))| {
+        if
+        after_chunk.split_once(|c:char|c.is_lowercase()).unwrap_or_default().0 !=
+        before_chunk.split_once(|c:char|c.is_lowercase()).unwrap_or_default().0 {0}else{
         diff::chars(after_chunk_filtered, &before_chunk_filtered)
           .into_iter()
           .filter(|i| matches!(i, diff::Result::Both(c, _)
           // `is_lowercase` increases accuracy for some trigger function diffs
           if c.is_lowercase() || c.is_numeric()))
-          .count()
+          .count()}
       })
       .unwrap_or((0,&default));
 
@@ -151,8 +158,60 @@ pub fn check_dump_diff(conn: &mut PgConnection, mut before: String, name: &str)
   panic!("{output}");
 }
 
-// todo inline?
-fn chunks<'a>(dump: &'a str) -> impl Iterator<Item = Cow<'a, str>> {
+fn process_chunk<'a>(result: &'a str) -> Cow<'a, str> {
+  if result.starts_with("CREATE TABLE ") {
+    // Allow column order to change
+    let mut lines = result
+      .lines()
+      .map(|line| line.strip_suffix(',').unwrap_or(line))
+      .collect::<Vec<_>>();
+    lines.sort_unstable_by_key(|line| -> (u8, &str) {
+      let placement = match line.chars().next() {
+        Some('C') => 0,
+        Some(' ') => 1,
+        Some(')') => 2,
+        _ => panic!("unrecognized part of `CREATE TABLE` statement: {line}"),
+      };
+      (placement, line)
+    });
+    Cow::Owned(lines.join("\n"))
+  } else if result.starts_with("CREATE VIEW") || result.starts_with("CREATE OR REPLACE VIEW") {
+    // Allow column order to change
+    let is_simple_select_statement = result
+      .lines()
+      .enumerate()
+      .all(|(i, mut line)| {
+        line = line.trim_start();
+        match (i, line.chars().next()) {
+          (0, Some('C')) => true, // create
+          (1, Some('S')) => true, // select
+          (_, Some('F')) if line.ends_with(';') => true, // from
+          (_, Some(c)) if c.is_lowercase() => true, // column name
+          _ => false
+        }
+      });
+    if is_simple_select_statement {
+      let mut lines = result
+        .lines()
+        .map(|line| line.strip_suffix(',').unwrap_or(line))
+        .collect::<Vec<_>>();
+      lines.sort_unstable_by_key(|line| -> (u8, &str) {
+        let placement = match line.trim_start().chars().next() {
+          Some('C') => 0,
+          Some('S') => 1,
+          Some('F') => 3,
+          _ => 2,
+        };
+        (placement, line)
+      });
+      Cow::Owned(lines.join("\n"))
+    }else{Cow::Borrowed(result)}
+  } else {
+    Cow::Borrowed(result)
+  }
+}
+
+fn chunks(dump: &str) -> impl Iterator<Item = &str> {
   let mut remaining = dump;
   std::iter::from_fn(move || {
     remaining = remaining.trim_start();
@@ -162,56 +221,7 @@ fn chunks<'a>(dump: &'a str) -> impl Iterator<Item = Cow<'a, str>> {
     // `a` can't be empty because of trim_start
     let (result, after_result) = remaining.split_once("\n\n")?;
     remaining = after_result;
-    Some(if result.starts_with("CREATE TABLE ") {
-      // Allow column order to change
-      let mut lines = result
-        .lines()
-        .map(|line| line.strip_suffix(',').unwrap_or(line))
-        .collect::<Vec<_>>();
-      lines.sort_unstable_by_key(|line| -> (u8, &str) {
-        let placement = match line.chars().next() {
-          Some('C') => 0,
-          Some(' ') => 1,
-          Some(')') => 2,
-          _ => panic!("unrecognized part of `CREATE TABLE` statement: {line}"),
-        };
-        (placement, line)
-      });
-      Cow::Owned(lines.join("\n"))
-    } else if result.starts_with("CREATE VIEW") || result.starts_with("CREATE OR REPLACE VIEW") {
-      // Allow column order to change
-      let is_simple_select_statement = result
-        .lines()
-        .enumerate()
-        .all(|(i, mut line)| {
-          line = line.trim_start();
-          match (i, line.chars().next()) {
-            (0, Some('C')) => true, // create
-            (1, Some('S')) => true, // select
-            (_, Some('F')) if line.ends_with(';') => true, // from
-            (_, Some(c)) if c.is_lowercase() => true, // column name
-            _ => false
-          }
-        });
-      if is_simple_select_statement {
-        let mut lines = result
-          .lines()
-          .map(|line| line.strip_suffix(',').unwrap_or(line))
-          .collect::<Vec<_>>();
-        lines.sort_unstable_by_key(|line| -> (u8, &str) {
-          let placement = match line.trim_start().chars().next() {
-            Some('C') => 0,
-            Some('S') => 1,
-            Some('F') => 3,
-            _ => 2,
-          };
-          (placement, line)
-        });
-        Cow::Owned(lines.join("\n"))
-      }else{Cow::Borrowed(result)}
-    } else {
-      Cow::Borrowed(result)
-    })
+    Some(result)
   })
 }