feat: support leading dynamic section when sourcing

This does the same thing that ShellCheck does ([here](https://github.com/koalaman/shellcheck/blob/ba86c6363c30a5dbefd0b8b9a7c5f4ab0478dc91/src/ShellCheck/Parser.hs#L2277-L2283)).

`To support the common pattern of . "$CONFIGDIR/mylib.sh", ShellCheck strips one leading, dynamic section before trying to locate the rest.`

fixes #926, fixes #659

fix: handle leading dynamic source paths when concatenating

This fixes `${var}/path` and `"${var}"/path` as well as countless variations of these patterns

Note: this turned out to be rather complex task, so it's broken out into a seperate function, which allows for early returns

refactor: move resolveStaticString to util/tree-sitter.ts

This seemed the most appropriate place for it.

tests: fix existing snapshot and add test for dynamic source paths

Adds a simple test for dynamic source paths and updates the snapshot to match new tests / behaivor.

Note: all the line numbers in the snapshot increased by 2 because I added two new lines (the test and a blank one)

tests: add new test in fixtures/sourcing.sh

I added this to the bottom of the file to minimize snapshot diffs. they're large enough as it is.

Author: aarondill

Diff for: server/src/__tests__/analyzer.test.ts

@@ -123,6 +123,28 @@ describe('analyze', () => {
           "severity": 3,
           "source": "bash-language-server",
         },
+        {
+          "message": "Source command could not be analyzed: failed to resolve path.
+
+      Consider adding a ShellCheck directive above this line to fix or ignore this:
+      # shellcheck source=/my-file.sh # specify the file to source
+      # shellcheck source-path=my_script_folder # specify the folder to search in
+      # shellcheck source=/dev/null # to ignore the error
+
+      Disable this message by changing the configuration option "enableSourceErrorDiagnostics"",
+          "range": {
+            "end": {
+              "character": 49,
+              "line": 26,
+            },
+            "start": {
+              "character": 0,
+              "line": 26,
+            },
+          },
+          "severity": 3,
+          "source": "bash-language-server",
+        },
       ]
     `)
 
@@ -847,6 +869,7 @@ describe('initiateBackgroundAnalysis', () => {
       [expect.stringContaining('parse-problems.sh: syntax error')],
       [expect.stringContaining('sourcing.sh line 16: failed to resolve path')],
       [expect.stringContaining('sourcing.sh line 21: non-constant source not supported')],
+      [expect.stringContaining('sourcing.sh line 26: failed to resolve path')],
     ])
 
     // Intro, stats on glob, one file skipped due to shebang, and outro

Diff for: server/src/util/__tests__/__snapshots__/sourcing.test.ts.snap

@@ -86,16 +86,30 @@ exports[`getSourcedUris returns a set of sourced files (but ignores some unhandl
     },
     "uri": null,
   },
+  {
+    "error": null,
+    "range": {
+      "end": {
+        "character": 39,
+        "line": 15,
+      },
+      "start": {
+        "character": 6,
+        "line": 15,
+      },
+    },
+    "uri": "file:///Users/bash/issue-926.sh",
+  },
   {
     "error": "non-constant source not supported",
     "range": {
       "end": {
         "character": 66,
-        "line": 16,
+        "line": 18,
       },
       "start": {
         "character": 49,
-        "line": 16,
+        "line": 18,
       },
     },
     "uri": null,
@@ -105,11 +119,11 @@ exports[`getSourcedUris returns a set of sourced files (but ignores some unhandl
     "range": {
       "end": {
         "character": 66,
-        "line": 18,
+        "line": 20,
       },
       "start": {
         "character": 6,
-        "line": 18,
+        "line": 20,
       },
     },
     "uri": null,
@@ -119,11 +133,11 @@ exports[`getSourcedUris returns a set of sourced files (but ignores some unhandl
     "range": {
       "end": {
         "character": 30,
-        "line": 25,
+        "line": 27,
       },
       "start": {
         "character": 8,
-        "line": 25,
+        "line": 27,
       },
     },
     "uri": "file:///Users/bash/issue206.sh",
@@ -133,53 +147,53 @@ exports[`getSourcedUris returns a set of sourced files (but ignores some unhandl
     "range": {
       "end": {
         "character": 22,
-        "line": 47,
+        "line": 49,
       },
       "start": {
         "character": 8,
-        "line": 47,
+        "line": 49,
       },
     },
     "uri": null,
   },
   {
-    "error": "non-constant source not supported",
+    "error": null,
     "range": {
       "end": {
         "character": 39,
-        "line": 59,
+        "line": 61,
       },
       "start": {
         "character": 8,
-        "line": 59,
+        "line": 61,
       },
     },
-    "uri": null,
+    "uri": "file:///Users/bash/staging.sh",
   },
   {
-    "error": "non-constant source not supported",
+    "error": null,
     "range": {
       "end": {
         "character": 42,
-        "line": 62,
+        "line": 64,
       },
       "start": {
         "character": 8,
-        "line": 62,
+        "line": 64,
       },
     },
-    "uri": null,
+    "uri": "file:///Users/bash/production.sh",
   },
   {
     "error": "non-constant source not supported",
     "range": {
       "end": {
         "character": 67,
-        "line": 89,
+        "line": 91,
       },
       "start": {
         "character": 10,
-        "line": 89,
+        "line": 91,
       },
     },
     "uri": null,

Diff for: server/src/util/__tests__/sourcing.test.ts

@@ -46,6 +46,8 @@ describe('getSourcedUris', () => {
 
       source "$LIBPATH" # dynamic imports not supported
 
+      source "$SCRIPT_DIR"/issue-926.sh # remove leading dynamic segment
+
       # conditional is currently not supported
       if [[ -z $__COMPLETION_LIB_LOADED ]]; then source "$LIBPATH" ; fi
 
@@ -144,7 +146,10 @@ describe('getSourcedUris', () => {
         "file:///Users/bash/x",
         "file:///Users/scripts/release-client.sh",
         "file:///Users/bash-user/myscript",
+        "file:///Users/bash/issue-926.sh",
         "file:///Users/bash/issue206.sh",
+        "file:///Users/bash/staging.sh",
+        "file:///Users/bash/production.sh",
       }
     `)
 

Diff for: server/src/util/sourcing.ts

@@ -102,20 +102,32 @@ function getSourcedPathInfoFromNode({
         }
       }
 
-      if (argumentNode.type === 'word') {
+      const strValue = TreeSitterUtil.resolveStaticString(argumentNode)
+      if (strValue !== null) {
         return {
-          sourcedPath: argumentNode.text,
+          sourcedPath: strValue,
         }
       }
 
-      if (argumentNode.type === 'string' || argumentNode.type === 'raw_string') {
-        const children = argumentNode.namedChildren
-        if (
-          children.length === 0 ||
-          (children.length === 1 && children[0].type === 'string_content')
-        ) {
+      // Strip one leading dynamic section.
+      if (argumentNode.type === 'string' && argumentNode.namedChildren.length === 1) {
+        const [variableNode] = argumentNode.namedChildren
+        if (TreeSitterUtil.isExpansion(variableNode)) {
+          const stringContents = argumentNode.text.slice(1, -1)
+          if (stringContents.startsWith(`${variableNode.text}/`)) {
+            return {
+              sourcedPath: `.${stringContents.slice(variableNode.text.length)}`,
+            }
+          }
+        }
+      }
+
+      if (argumentNode.type === 'concatenation') {
+        // Strip one leading dynamic section from a concatenation node.
+        const sourcedPath = resolveSourceFromConcatenation(argumentNode)
+        if (sourcedPath) {
           return {
-            sourcedPath: argumentNode.text.slice(1, -1),
+            sourcedPath,
           }
         }
       }
@@ -171,3 +183,49 @@ function resolveSourcedUri({
 
   return null
 }
+
+/*
+ * Resolves the source path from a concatenation node, stripping a leading dynamic directory segment.
+ * Returns null if the source path can't be statically determined after stripping a segment.
+ * Note: If a non-concatenation node is passed, null will be returned. This is likely a programmer error.
+ */
+function resolveSourceFromConcatenation(node: Parser.SyntaxNode): string | null {
+  if (node.type !== 'concatenation') return null
+  const stringValue = TreeSitterUtil.resolveStaticString(node)
+  if (stringValue !== null) return stringValue // This string is fully static.
+
+  const values: string[] = []
+  // Since the string must begin with the variable, the variable must be in the first child.
+  const [firstNode, ...rest] = node.namedChildren
+  // The first child is static, this means one of the other children is not!
+  if (TreeSitterUtil.resolveStaticString(firstNode) !== null) return null
+
+  // if the string is unquoted, the first child is the variable, so there's no more text in it.
+  if (!TreeSitterUtil.isExpansion(firstNode)) {
+    if (firstNode.namedChildCount > 1) return null // Only one variable is allowed.
+    // Since the string must begin with the variable, the variable must be first child.
+    const variableNode = firstNode.namedChildren[0] // Get the variable (quoted case)
+    // This is command substitution!
+    if (!TreeSitterUtil.isExpansion(variableNode)) return null
+    const stringContents = firstNode.text.slice(1, -1)
+    // The string doesn't start with the variable!
+    if (!stringContents.startsWith(variableNode.text)) return null
+    // Get the remaining static portion the string
+    values.push(stringContents.slice(variableNode.text.length))
+  }
+
+  for (const child of rest) {
+    const value = TreeSitterUtil.resolveStaticString(child)
+    // The other values weren't statically determinable!
+    if (value === null) return null
+    values.push(value)
+  }
+
+  // Join all our found static values together.
+  const staticResult = values.join('')
+  // The path starts with slash, so trim the leading variable and replace with a dot
+  if (staticResult.startsWith('/')) return `.${staticResult}`
+  // The path doesn't start with a slash, so it's invalid
+  // PERF: can we fail earlier than this?
+  return null
+}

Diff for: server/src/util/tree-sitter.ts

@@ -57,6 +57,16 @@ export function isVariableInReadCommand(n: SyntaxNode): boolean {
   return false
 }
 
+export function isExpansion(n: SyntaxNode): boolean {
+  switch (n.type) {
+    case 'expansion':
+    case 'simple_expansion':
+      return true
+    default:
+      return false
+  }
+}
+
 export function findParent(
   start: SyntaxNode,
   predicate: (n: SyntaxNode) => boolean,
@@ -78,3 +88,29 @@ export function findParentOfType(start: SyntaxNode, type: string | string[]) {
 
   return findParent(start, (n) => type.includes(n.type))
 }
+
+/**
+ * Resolves the full string value of a node
+ * Returns null if the value can't be statically determined (ie, it contains a variable or command substition).
+ * Supports: word, string, raw_string, and concatenation
+ */
+export function resolveStaticString(node: SyntaxNode): string | null {
+  if (node.type === 'concatenation') {
+    const values = []
+    for (const child of node.namedChildren) {
+      const value = resolveStaticString(child)
+      if (value === null) return null
+      values.push(value)
+    }
+    return values.join('')
+  }
+  if (node.type === 'word') return node.text
+  if (node.type === 'string' || node.type === 'raw_string') {
+    if (node.namedChildCount === 0) return node.text.slice(1, -1)
+    const children = node.namedChildren
+    if (children.length === 1 && children[0].type === 'string_content')
+      return children[0].text
+    return null
+  }
+  return null
+}

Diff for: testing/fixtures/sourcing.sh

@@ -23,3 +23,5 @@ loadlib () {
 }
 
 loadlib "issue206"
+
+source $SCRIPT_DIR/tag-release.inc with arguments