feat(rules): add ban-drop-table (#207)

Author: juleswritescode

crates/pglt_analyser/src/lint/safety.rs

@@ -3,4 +3,5 @@
 use pglt_analyse::declare_lint_group;
 pub mod ban_drop_column;
 pub mod ban_drop_not_null;
-declare_lint_group! { pub Safety { name : "safety" , rules : [self :: ban_drop_column :: BanDropColumn , self :: ban_drop_not_null :: BanDropNotNull ,] } }
+pub mod ban_drop_table;
+declare_lint_group! { pub Safety { name : "safety" , rules : [self :: ban_drop_column :: BanDropColumn , self :: ban_drop_not_null :: BanDropNotNull , self :: ban_drop_table :: BanDropTable ,] } }

crates/pglt_analyser/src/lint/safety/ban_drop_table.rs

@@ -0,0 +1,52 @@
+use pglt_analyse::{context::RuleContext, declare_lint_rule, Rule, RuleDiagnostic, RuleSource};
+use pglt_console::markup;
+
+declare_lint_rule! {
+    /// Dropping a table may break existing clients.
+    ///
+    /// Update your application code to no longer read or write the table.
+    ///
+    /// Once the table is no longer needed, you can delete it by running the command "DROP TABLE mytable;".
+    ///
+    /// This command will permanently remove the table from the database and all its contents.
+    /// Be sure to back up the table before deleting it, just in case you need to restore it in the future.
+    ///
+    /// ## Examples
+    /// ```sql,expect_diagnostic
+    /// drop table some_table;
+    /// ```
+    pub BanDropTable {
+        version: "next",
+        name: "banDropTable",
+        recommended: true,
+        sources: &[RuleSource::Squawk("ban-drop-table")],
+    }
+}
+
+impl Rule for BanDropTable {
+    type Options = ();
+
+    fn run(ctx: &RuleContext<Self>) -> Vec<RuleDiagnostic> {
+        let mut diagnostics = vec![];
+
+        if let pglt_query_ext::NodeEnum::DropStmt(stmt) = &ctx.stmt() {
+            if stmt.remove_type() == pglt_query_ext::protobuf::ObjectType::ObjectTable {
+                diagnostics.push(
+                    RuleDiagnostic::new(
+                        rule_category!(),
+                        None,
+                        markup! {
+                            "Dropping a table may break existing clients."
+                        },
+                    )
+                    .detail(
+                        None,
+                        "Update your application code to no longer read or write the table, and only then delete the table. Be sure to create a backup.",
+                    ),
+                );
+            }
+        }
+
+        diagnostics
+    }
+}

crates/pglt_analyser/src/options.rs

@@ -5,3 +5,4 @@ pub type BanDropColumn =
     <lint::safety::ban_drop_column::BanDropColumn as pglt_analyse::Rule>::Options;
 pub type BanDropNotNull =
     <lint::safety::ban_drop_not_null::BanDropNotNull as pglt_analyse::Rule>::Options;
+pub type BanDropTable = <lint::safety::ban_drop_table::BanDropTable as pglt_analyse::Rule>::Options;

crates/pglt_analyser/tests/specs/safety/banDropTable/basic.sql

@@ -0,0 +1,2 @@
+-- expect_only_lint/safety/banDropTable
+drop table test;

crates/pglt_analyser/tests/specs/safety/banDropTable/basic.sql.snap

@@ -0,0 +1,16 @@
+---
+source: crates/pglt_analyser/tests/rules_tests.rs
+expression: snapshot
+---
+# Input
+```
+-- expect_only_lint/safety/banDropTable
+drop table test;
+```
+
+# Diagnostics
+lint/safety/banDropTable ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  × Dropping a table may break existing clients.
+  
+  i Update your application code to no longer read or write the table, and only then delete the table. Be sure to create a backup.

crates/pglt_configuration/src/analyser/linter/rules.rs

@@ -149,18 +149,25 @@ pub struct Safety {
     #[doc = "Dropping a NOT NULL constraint may break existing clients."]
     #[serde(skip_serializing_if = "Option::is_none")]
     pub ban_drop_not_null: Option<RuleConfiguration<pglt_analyser::options::BanDropNotNull>>,
+    #[doc = "Dropping a table may break existing clients."]
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub ban_drop_table: Option<RuleConfiguration<pglt_analyser::options::BanDropTable>>,
 }
 impl Safety {
     const GROUP_NAME: &'static str = "safety";
-    pub(crate) const GROUP_RULES: &'static [&'static str] = &["banDropColumn", "banDropNotNull"];
-    const RECOMMENDED_RULES: &'static [&'static str] = &["banDropColumn", "banDropNotNull"];
+    pub(crate) const GROUP_RULES: &'static [&'static str] =
+        &["banDropColumn", "banDropNotNull", "banDropTable"];
+    const RECOMMENDED_RULES: &'static [&'static str] =
+        &["banDropColumn", "banDropNotNull", "banDropTable"];
     const RECOMMENDED_RULES_AS_FILTERS: &'static [RuleFilter<'static>] = &[
         RuleFilter::Rule(Self::GROUP_NAME, Self::GROUP_RULES[0]),
         RuleFilter::Rule(Self::GROUP_NAME, Self::GROUP_RULES[1]),
+        RuleFilter::Rule(Self::GROUP_NAME, Self::GROUP_RULES[2]),
     ];
     const ALL_RULES_AS_FILTERS: &'static [RuleFilter<'static>] = &[
         RuleFilter::Rule(Self::GROUP_NAME, Self::GROUP_RULES[0]),
         RuleFilter::Rule(Self::GROUP_NAME, Self::GROUP_RULES[1]),
+        RuleFilter::Rule(Self::GROUP_NAME, Self::GROUP_RULES[2]),
     ];
     #[doc = r" Retrieves the recommended rules"]
     pub(crate) fn is_recommended_true(&self) -> bool {
@@ -187,6 +194,11 @@ impl Safety {
                 index_set.insert(RuleFilter::Rule(Self::GROUP_NAME, Self::GROUP_RULES[1]));
             }
         }
+        if let Some(rule) = self.ban_drop_table.as_ref() {
+            if rule.is_enabled() {
+                index_set.insert(RuleFilter::Rule(Self::GROUP_NAME, Self::GROUP_RULES[2]));
+            }
+        }
         index_set
     }
     pub(crate) fn get_disabled_rules(&self) -> FxHashSet<RuleFilter<'static>> {
@@ -201,6 +213,11 @@ impl Safety {
                 index_set.insert(RuleFilter::Rule(Self::GROUP_NAME, Self::GROUP_RULES[1]));
             }
         }
+        if let Some(rule) = self.ban_drop_table.as_ref() {
+            if rule.is_disabled() {
+                index_set.insert(RuleFilter::Rule(Self::GROUP_NAME, Self::GROUP_RULES[2]));
+            }
+        }
         index_set
     }
     #[doc = r" Checks if, given a rule name, matches one of the rules contained in this category"]
@@ -245,6 +262,10 @@ impl Safety {
                 .ban_drop_not_null
                 .as_ref()
                 .map(|conf| (conf.level(), conf.get_options())),
+            "banDropTable" => self
+                .ban_drop_table
+                .as_ref()
+                .map(|conf| (conf.level(), conf.get_options())),
             _ => None,
         }
     }

crates/pglt_diagnostics_categories/src/categories.rs

@@ -15,6 +15,7 @@
 define_categories! {
     "lint/safety/banDropColumn": "https://pglt.dev/linter/rules/ban-drop-column",
     "lint/safety/banDropNotNull": "https://pglt.dev/linter/rules/ban-drop-not-null",
+    "lint/safety/banDropTable": "https://pglt.dev/linter/rules/ban-drop-table",
     // end lint rules
     ;
     // General categories